Eating Machine

This trope is for robots and cyborgs with primarily robotic bodies that consume human food and drink.

This is very common for a Ridiculously Human Robot who may need to eat food to maintain The Masquerade, but it's certainly not limited to that trope. Some robots consume food as a power source (Calories powering machines is something that exists in the real world, though in very early stages) either for convenience (or rarely for horror). Other robots may eat food they have no way of processing and no logical need for as pure Rule of Funny hedonism and to anthropomorphize otherwise non-human machines. Despite being unable to digest food, don't be surprised if caffeine, sugar, or alcohol still somehow affects a robot's behavior.

Many robots that can eat food also have a distinct preference, whether it be for something that's easy for their system to convert to energy or whether it be just the same tasty junk foods that humans love. Alcohol and sweets are popular for both reasons.

Examples of Eating Machine include:

Anime and Manga

All Purpose Cultural Cat Girl Nuku Nuku: Nuku Nuku is a cyborg housing only a rescued kitten's brain (and maybe some other organs), but she eats just like a normal teenage girl would. Well, with some feline preferences.
Doraemon needs to eat to function like a human and his favorite food is dorayaki.
Rozen Maiden, all of them. Though maybe it's due to their Magitek-ness.
Chachamaru in Mahou Sensei Negima can eat and drink though she claims she has no sense of taste. Apparently it's to feel more human. Later, she can be seen licking an ice cream cone and is in the school's tea club. By the time of the ice cream event, she may actually be able to taste it considering the numerous upgrades.

Comic Books

In the Marvel Universe, the original Human Torch (who, despite his name, was an android) used to eat and drink.
Aaron Stack, a.k.a. "Machine Man" from Nextwave. "My robot brain needs beer!" In Marvel Zombies 3, however, he stated "I have no stomach, but I must barf."

Film

Subverted in A.I.: Artificial Intelligence: the android David tries to eat spinach to fit in with his human family, but ends up causing his machinery to jam on it, so a tech-support team has to open him up and dig the spinach out. Woops.
Subverted in the obscure B-movie sequel, Class of 1999 2: The Substitute. It is believed that the huge substitute teacher is an android and he's a Big Eater, he even says "My body turns food into fuel quite quickly," but it turns out he's just a man who thinks he's an android.

Literature

In Isaac Asimov's The Caves of Steel, R. Daneel Olivav is a human-shaped android who can "consume" food and drink to imitate a human. He actually stores the food in a bag within his stomach which he regularly empties. He even offers the food from the bag to his human friend, explaining that it's untouched and fit for consumption. The human obviously refuses.
Isaac in The Dark Side of the Sun can "derive power from the calorific content of organic substances", and even seems to have a bit of a palate when it comes to alcohol.

"Old Overcoat. The genuine stuff. Two glasses and you rise up on a pillar of flame."

In The Positronic Man, co-written by Isaac Asimov and Robert Silverberg (and based on Asimov's short story Bicentennial Man), a robot eventually upgrades himself with a device that converts food to energy.

Live-Action TV

Data in Star Trek: The Next Generation can consume food and drink to appear more human and put others at ease. He also appears to have taste buds; when he gets his emotion chip in Star Trek Generations, he realises he "hates" a certain drink.
The 'Bots on Mystery Science Theater 3000 are like this, especially Gypsy.
Kryten of Red Dwarf doesn't normally eat or drink, but it turns out that Mamosian cuisine, including the telepathic wine, is suitable for droids. An earlier episode has him consuming a beverage especially designed to function on droids like alcohol does on a human system.
In an episode of Small Wonder, Ted modified Vicki to extract energy from food and use beverages as coolants.
In The Sarah Connor Chronicles, Cameron is able to eat food, though it is not made clear whether she does this to blend in with humans or if she gets some benefit from this. At one point she is glitching due to damage to her processor and is convinced that she is actually human, and when presented with a large plate of food she says she isn't hungry.

Tabletop Games

The Cryx Kraken Colossal from WarMachine has a special rule called "Meat Fuelled" - allowing it to gain Focus Points when it kills a Living enemy Model. Essentially, it's a giant robot that eats people.

Toys

Played with in Bionicle. The Matoran were shown fishing and there was mention of food in the first few years of the story, but the characters were never seen eating the food. Since Matoran must wear their masks at all times and wouldn't be able to put food into their mouths, this resulted in a large dose of Fridge Logic... until it was revealed that they consume food by absorbing it through the palms of their hands.

Video Games

In general, nearly every video game that features both biological and mechanical protagonists and food- or drink-based power-ups is subject to this. Examples include Chrono Trigger, Pokémon, Persona 3, Super Smash Bros. Brawl, etc.
In the Five Nights at Freddy's franchise, Chica zigzags this Trope. She loves to eat pizza, but with no metabolism or digestive system, doing so damages her innards and circuitry.

Web Comics

Questionable Content: Pintsize loves to pig out on cakes despite having no stomach or really even containing space for the food, leaving Marten to have to power him off and clean him out more than once.
- Pintsize and the other AnthroPC's have a rather ambiguous attitude towards eating stuff. Early on in the comic, Pintsize claim to be able to eat and taste food, thanks to an onboard spectrometer - he stores it in a compartment of his chest, then evacuates it later. It's somewhat gross. Later, however, he gets a new chassis, which apparently lacks this function, but that doesn't stop him from eating - just makes it a bad idea. As he is heard saying once, "That was SO worth the massive motherboard damage..."
Some of the robots of Bob and George subvert this trope. Megaman eats ice cream by the gallon daily, at first seeming like this trope. As it turns out Dr. Light built him to convert ice cream into fuel.
Ping in Megatokyo, to Miho's initial surprise. She can actually derive energy from sugars, and she loves cake.
In Quentyn Quinn, Space Ranger, the main character's robot helper orders a banana sundae. It explains that it has the capacity to enjoy the sundae- as a work of art, not as nourishment.

Western Animation

Invader Zim: GIR is an example of a robot that has no use for food but pigs out on it anyway to the point of removing useful system components to make more room for stored snacks.
Futurama: Bender (and all robots) is designed to run off booze. This doesn't stop him from getting drunk or being an alcoholic, though. (Actually, Bender only gets drunk if he doesn't drink alcohol.)
Subversion in My Life as a Teenage Robot: Trying to fit in with her new human friends Jenny eats an ice cream cone (in one bite) but as soon as they look away she opens a door in her chest and throws the ice cream away.
Octus from Sym-Bionic Titan is seen eating icecream bars in one episode.
Cyborg from Teen Titans is a Big Eater. Justifiable, as he's not entirely machine.
The cars in Cars not only consume fuel (they drink it from a straw rather than taking it in through their gas valves) but also other metal objects like nuts and bolts, as with "human" food including fruits and vegetables, and meat. Except nobody knows where their meat products come from considering the fact that the animals in their world are also vehicles like them, with their cattle being portrayed as either farm or construction equipment.
- Cars kill farm and construction equipment for food? Who wants tractorburgers? Come and get 'em! Only $2.50!

Real Life

A company is developing a biomass-fueled robotic drone called EATR. It can run on anything from conventional fuels to scavenged leaves and twigs. Early news articles sensationally (and inaccurately) reported that it was designed to eat meat—including human corpses.
The mechanical sculpture Cloaca No. 5 by Wim Delvoye.
There are also electronic devices being developed which can run off the glucose in human blood (potential applications include electronic tattoos and Hollywood Cyborg style prosthetics).