Cosplay is a HUGE subculture. Why? I feel like it's clear, because anyone seeing it for the first time may find it weird. Anyone trying it for the first time might also find it weird. So it definitely doesn't exist in main stream - well, not really acknowledged, or it might be frowned upon if you do it as an adult or something - of course, unless you're in this subculture! Similar to anime fans, but can include gamers and other things like this. One thing that stood out to me right away was the fact that I didn't know who most of the people were dressing up as (besides the people dressing up as people from games), so I'm clearly not part of this subculture.