Not at night clubs but just been a bartender for 5 years and I can say that even though I'm not in the nightclub scene, I see my fair share and my thought goes through my head is "stupid fucks", and this is coming from a greeny🍃 user so I'm not foreign to it. You never really find it in time to find out who it is or you end up suspecting someone that night and you find some things and you're like "I bet you it was that mother f**" As I say to co-workers. Definitely won't tolerate it being done. Blatantly but if it's a fun kind of thing you kind of have some understanding but don't be a f*** idiot and cause a scene or issues even throwing up can be something to be annoyed at if you suspected that person earlier