Now I come from NW WorldClub land where we have self serve everything (except in a few outstations where tending is mandated by local laws). So it is a bit odd when I enter a PC and see people tipping.
Generally, I don't tip. I usually only have one or two drinks and, to me, that just doesn't warrant a tip in a lounge. If I'm there for a long while, order a bunch of things for friends/acquaintances, or spend a lot of time taking with the tender, then perhaps I would consider a tip. But generally, I don't. I'm just used to not having to reach for my wallet once I'm actually
in the club. That's part of the reason why I buy a membership.