Cosplay is a form of high fashion, so it can produce the same internal and external pressures (comparing yourself to artist's illustrations, the strange dynamics between a model and an audience, etc.) I think what makes this less obvious is that for many years it was largely non-commercial high-fashion, the models making their own copies of clothes that were never available for sale and that were created by a character-designer not a fashion-designer.

The original idea behind cosplay was that it was a way for the model to show appreciation for a character; sometimes the character did not have the same sex as the model. Crossplay was initially a positive influence because it made models less anxious about things that are difficult to change, such as their physical structure, when cosplaying as a character that they loved but did not really look like. Everyone laughed at "Sailor Bubba", but it was more of a relief sort of laughter; if a fat man can be Sailor Moon for a day, why can't you? However, fashion can be very competitive, so competitive crossplay also developed.

Much like with traditional high-fashion, many of the models are young, and may not know how to cope with these sort of pressures. When they reach out for help, these ideas are what they receive. :(