I was watching the episode with Danny DeVito the other day, and concentrating on the background instead of the foreground action, and it makes the whole scene seem very weird. There's a bunch of other guests, none of whom we've ever seen before, who are just sitting around chatting while this bizarre scene with an aging, crying, short, bald stripper plays out in the same room as them. None of them seem to be interested in what's going on, nobody else in the room tries to intervene.
Generally in Friends, there are scenes when one of the two main apartments hosts a party, and a bunch of people turn up that we've never seen before. There is at least one episode where Chandler tries to chat up a woman in his own apartment and she just walks away. Who does that? When you're a guest in someone's home?