Menswear Ghetto

On Virtual Paper Doll communities, there's often a lack of masculine clothing. This can be because:

Most of the members are female or crossplayers.
Feminine clothing is more fun to design because it allows for things like frills and sequins.
Men simply don't have as many clothing options as women, not being able to wear skirts without allegations of transvestism.

It can be very restricting if this is a website where male avatar bases can't wear female clothing.

Examples of Menswear Ghetto include:

Literature

One book to learn Chinese teaches them the word "Unfair" with a picture of the menswear department next to womenswear.

Video Games

In Magician's Quest: Mysterious Times, there's a whole sub-type of clothing dedicated to skirts, but no shorts. Also, the vast majority of the "long clothes"-style outfits are dresses. However, male characters can still wear anything.
Averted in The World Ends With You: given a high enough Bravery stat, any character can wear anything. Gameplay and Story Segregation, however, prevents hilarity from ensuing.
Averted with World of Warcraft, in which anyone can wear anything regardless of gender; however, the same item of clothing in the inventory becomes a wholly different thing on a female character, looks wise, than on a male.
- For an example, go to Wow Head or another World Of Warcraft database and look up "Black Mageweave Leggings". On a female character, these will look like a pair of sexy black thighhighs. On a male character, they look like...sweatpants.
- Similarly, The Elder Scrolls IV: Oblivion gets around this problem by having clothes that transform depending on what gender the wearer is, which means that most clothing for the lower body slot shows up as pants on a man but a skirt on a woman. And since any NPC's clothes are items that can be taken from them if they're killed, it's entirely possible for you to kill a random townswoman (And don't say you haven't), steal her skirt, and put it on as pants. Don't ask how that works.
Touhou Project character creator create.swf also suffers from this. Justified, though, given the cast....

Web Comics

Inversion: When Phil and Kaja Foglio introduced a fashion-designer clank into the Girl Genius side-stories, Gil got two pages of outfits. Interestingly, Zeetha, Krosp and Agatha only got one page each. Nice turn-about.

Web Original

This used to be in effect on Subeta, until the artists heard complaints about it and took action. Fortunately, their clothing has always been unisex.
On meez, male avatars don't have half the options females do. This is particularly confusing considering that things like certain sneakers and sunglasses are restricted to females.
In the early days of there were separate clothes for male and female avatars on Gaia Online, with only the appropriate clothing showing up in stores, so if you wanted to see all the clothing, you had to have two accounts. They stopped doing that pretty early on, and all later clothing is unisex.
- Many users will agree, though, that the female clothes tend to be superior. Even the unisex clothes often look better on female avatars, unless the clothes were designed specifically with the male avatar in mind.
Kingdom of Loathing plays this straight, but gets around it: for every skirt (which only drop for girl characters), there is a corresponding kilt (which only drop for boys). Any given skirt/kilt combo will have the same stats as each other and the corresponding unisex pants.
- And while there's a few items that only drop for/can only be crafted by one gender, once they enter the game world they can be worn by anyone. There's one item that penalizes males for wearing it, though.
PangYa will sometimes go months before adding outfits for males while the girls can get new outfits nearly every two weeks.
Second Life falls victim to this, despite the fact that there are many male characters, as the ingame clothing economy is tailored largely towards females; probably because they generally spend more energy and money finding clothes. This is especially noticable when new male players are trying to find 'freebies'.