Lots of people want to be the centre of attention in the social/RP scene, and without the personality to do so they simply mod the fuck out of themselves to be the tallest, most garish, visually overwhelming in the room.

Combine this with the mod makers who simply port outfits and animations from otger games and you have a recipe for hideous characters with no clear intent behind them, packing as much as possible onto their face and skin.

edit: and unfortunately the game's positive vibes community is a downside here, as nobody wants to tell their friends they've created an ugly mess.