Five-Finger Discount

"In this life, one thing counts
In the bank, large amounts
I'm afraid these don't grow on trees

You've got to pick a pocket or two!"

—Fagin, Oliver!

The preferred method a Street Urchin uses to acquire stuff—since they're too poor to afford it legitimately—is to sneak it out of their mark's pocket and/or into their own. A Rebellious Princess sometimes does this for the sheer thrill of it, or because they honestly believe they don't have to pay for anything; expect some kind of Freudian Excuse to come into play. The Kleptomaniac Hero also does this to anything that isn't nailed down and/or can be sold for money. Someone with Sticky Fingers does it merely because they want or are compelled to.

When this is done to a retail establishment, this is known as shoplifting.

Ballistic Discount is a subtrope which adds murder to the ensemble and will likely get you killed if you should ever try it in a real gun shop. Percussive Pickpocket is a method of invoking this trope where the theft is disguised as a harmless bump on the street.

Examples of Five-Finger Discount include:

Advertising

Some commercials for Burger King claims that the chain practices "reverse pickpocketing" by sneaking money back into their customers' pockets.

Anime and Manga

This is how Rurouni Kenshin meets Kid Samurai Yahiko—Kaoru reveals that Yahiko's Crash Into Hello was an attempt to rob him (though given that Kenshin just gave the kid his wallet afterwards, it's pretty obvious he knew).
At least one student in Great Teacher Onizuka has a habit of shoplifting because she feels neglected by her workaholic parents.
The Black Jack story "Tetsu of the Yamanote Line" revolves around the titular Tetsu, a notorious pickpocket, and his friendly rivalry with a police detective who's sworn to catch him red-handed. When Tetsu gets his fingers cut off after trying to rob some Yakuza, the detective brings in Black Jack to fix Tetsu's fingers.

Comics

In Runaways, when the protagonists go out to buy food, Nico warns them all "Remember, you're invisible to most adults until you start shoplifting, so go easy on the five finger discounts".

Film

Disney's Aladdin. Street Urchin Aladdin and his monkey friend Abu steal a melon for breakfast in the city's marketplace, as shown in this YouTube clip. After they meet Princess Jasmine, Abu snags some apples and gold pieces this way.
The Thief in The Thief and the Cobbler is such an inveterate kleptomaniac that he even picks his own pocket.
Young Charlie Chaplin in Shanghai Knights.
In Animal House, one of the characters steals food for a party by hiding it in his jacket. The check-out girl notices, but doesn't turn him in.
- It's even funnier than that: two of the items hidden in the guy's jacket are a couple of small roasts, and they're hidden so that they look like boobs.

Literature

In Oliver Twist, Oliver joins a street gang who are trained in the arts of pickpocketing.
- Perhaps in a Shout-Out to this, Law and Order: Criminal Intent runs across a similar pickpocketing training school when a body of one of its "students" turns up in the Cold Opening.
Take A Thief by Mercedes Lackey also features a pickpocketing training school that main character Skif attends for a while. Again, there's a lot of similarities to Oliver Twist.
In the third book of the Codex Alera, High Lady Antillus is bullying Rufus Scipio, a.k.a. Tavi. He responds by acting meek, and the moment she's out of earshot, pulls her purse out of his pocket. How else is the only Muggle in the setting going to get revenge on a Person of Mass Destruction? This turns out to be a major plot point.
In a short story by Roald Dahl, the narrator gives a hitchhiker a lift and has a rather interesting discussion with the guy, who is a professional ~~pickpocket~~ fingersmith. The hitchhiker is very proud of his work and is even able to remove the belt from the narrator without attracting attention. Apparently he makes a living by going to horse races and stealing from people who win several games (though he prides himself in never stealing from poor people or anyone who loses). At the end of the story, when a police officer writes down the narrator's information for speeding, the fingersmith steals said notes so they won't get caught.
"Fruit of the barrow is enough for a Borrible" is one of the proverbs of The Borribles, immortal elf-like Street Urchins living in the wainscoting of society, and whose entire culture is built around stealing what they need from the adults/humans around them.

Live Action TV

In Degrassi the Next Generation, Control Freak Liberty tries to make nice with the school bad boys. When she tries to impress them by saying she'll provide a "five-finger discount," they're hysterical that this dork thinks this phrase is cool. A few episodes later, as the bad boys are shoplifting, the ringleader flexes his fingers and says, as if he thinks it's cool, "I can get us a five-finger discount."
Walter's sister-in-law Marie in Breaking Bad is a chronic shoplifter.
This is part of Parker's repertoire in Leverage. They have an actual pickpocketing expert, Apollo Robbins, on staff to make sure it's done right. He appeared in one episode as Parker's Evil Counterpart in another crew.
Dawn in Buffy the Vampire Slayer turns out to have a bit of kleptomania, but after that little side plot is solved it's quickly forgotten.

Video Games

Lampshaded in the Discworld PC game: Rincewind remarks that lovable street urchins are well-known for that sort of thing.
The player character in games like Fable, Fallout, and Oblivion can steal just about everything not environment geometry as long as their dexterity is high enough and nobody's looking.
In Thief, Garrett usually aims for more lucrative jobs, but he's not above stealing from passerby when money's tight and the rent is due. In addition, he was recruited into the Keepers as a child because he was caught trying to make a grab from one.
Pretty much standard practice for beginner in Morrowind. Steal some stuff, hide it (AKA drop it in plain sight) and then sell it to someone to get money.
Luke of Tales of the Abyss is a Royal Brat who has been sequestered in his mansion for years ever since the attempted kidnapping. He doesn't really get the concept of paying for things, until he gets a rude awakening from an apple merchant.
You can pickpocket NPCs in Fallout 3. In a darkly comedic take on the Burger King example above, it's also possible to "reverse pickpocket" them, i.e. sneaking items into their possession, such as bombs about to go off. The game keeps track of how many times you've done this under "Pants Exploded", and awards the Psychotic Prankster achievement for pulling it off the first time.
- Planting items on NPCs is also useful for getting unique equipment from them (by giving them stronger but more common armor or stealing their ammo and planting a different weapon with some of its ammo, which the NPC will usually equip if you leave the building or town and come back). In some cases, you can also give skill-boosting equipment to characters who provide services based on those skills (most useful with Repair) or remove Haggle-boosting equipment from merchants.
In Assassin's Creed II and its two sequels Ezio Auditore can do this to passers-by to gain a few coins. Certain missions involve using the skill to surreptitiously acquire important items. Particularly satisfying, after bribing a herald to stop bad-mouthing the Assassins, you can turn around and lift your bribe right back out of his pocket.

Web Comics

Referred to as a "two-bicep discount" in The Bloody Nipple Saga.
Due to the art style, Haley Starshine of the Order of the Stick once refers to this as the three-finger discount.
Batman and Sons does this with "Don't Mess with Bats." After a bad day which gets Batman snarky, he gets on the nerves of Jesse Quick, Hourman and Dr. Mid-Nite by showing his hands "are quicker than" their eyes: he snatches Jesse's top while she runs at him, he gets Hourman's hourglass while he's making his threat (and he suddenly sees it's gone and on Batman, who goes "Tick Tock"), and he gets Dr. Mid-Nite's goggles, rendering him unable to see—and running into a tree.
In this strip of Life of Maid, Marisa, being... well, Marisa, decides to indulge in a spot of shoplifting, making off with a basket full of goods from Rinnosuke's store. Unfortunately for Marisa, Sakuya has just applied for a part-time job there in order to make up for the Scarlet Devil Mansion's expenses, and finds it quite easy to get Rinnosuke's goods back.
Early on in Newheimburg, Jack wanders around Newheimburg's World Fair and snatches 20 bucks off of a complete stranger.
Freefall had Sam Starfall the "larcenous squid" taking a little four fingers discount (those are bundles of tentacles, but he wears gloves) often, though sometimes it doesn't work, and sometimes ends in something strange.

Western Animation

On The Simpsons they have occasionally called it the four-fingered discount.
In Family Guy, Lois sneaks a ham into her purse because she can't afford it, but soon grows addicted to the sheer thrill of stealing.
Even though the H.I.V.E. kids in Teen Titans are doing a little more than shoplifting, they still claim to have purchased their stuff with a "five-finger discount".
Dijon from DuckTales (1987) is notorious for pilfering anything that isn't nailed down, and he'll pull the nails out it if it has value.
Dora the Explorer: Swiper, no swiping!

Real Life

Real Life: Name a teenaged celebrity, odds are they've been in the news for shoplifting.
Teenagers shoplifting is both Truth in Television and a stereotype. If you're a teenager and you enter a shop in the mall, you bet those super-nice staffers are watching your every move.
- Obviously they're not watching close enough! Ha Ha ha!