-Hangs around for the chat-
I don't cosplay or thrift shop, because I don't live in a place that actually has one less than 20 minutes of car-ride away, but I do wonder...

What has to be true to make it a "Thrift" shop, and not just a Shop-Shop?

Thrift shops/Charity shops get clothing and household items donated to them from ordinary citizens, and then resell those items at much cheaper prices than you'd be able to buy them in retail stores.

i don't cosplay, but i know someone that does do cosplay stuff.

do they sew their own stuff?

i mean, probably? i'd have to ask and they're more towards an acquaintance than a friend.