Every time I walk in, most people are in civvies. Not even outlandish ones that could look like a costume, but normal boring t-shirt and jeans type civvies.

It's rather immersion-breaking considering all the NPC's are in costume, and the ones outside even complain about not getting in without a costume.

I'd almost guess that to the majority of players (not characters) the T-shirt, civilian uniform is a "costume" and the main heroing outfit is the "casual" attire.

That doesn't really matter, because you are supposed to sport superheroing duds in the place.

It's a club. You mostly go places like that to hang out and have fun. Maybe the costume is just to prove you're a hero. *Shrug* If you can prove it otherwise, well, go on in.

For some heroes, "jeans and a t-shirt" IS their "csotume". (What doyou want? He's fourteen years old ... it's hard to afford a major designer's salary, on a ninth-grader's allowance ...)

It could be worse.

They could all be naked.

Because the club and other places like that are normally where heroes go to blow off steam. Those who have a secret identity might go in, in costume. Everybody needs a little downtime, superheroes included. Not even Defender spends 24/7 in his costume.

Catgirls have that base covered already. :p

Not just catgirls.

Don't forget the Succubi, Demons, Vampires, and Cat-girl-succubi-vampire-ninja-robots.