why are there people so open about being a lolicon
Because they enjoy the fashion. The same reason folks are open about being hipsters, emo, goth, punk, ect.
OP said “lolicon” not “lolita” those aren’t the same thing.
They arent? I had no idea
Lolicons want to fuck people that look or are young. Lolita is just another fashion trend.

Sometimes lolis (lolicon) dress as lolitas, and I thinks that’s where people get confused.