I think you're tipped for doing a good job and being friendly, not kissing
someones ass. That'd be more likely to induce vomiting instead. Obsequiousness
certainly turns my stomach :-P
Oh, and ahve you ever tried to tip a barman here in the UK? In all but the
best cocktail bars they stare at you as if you're mad. I actually had a guy
working in a pub refuse to take a $4 tip from me once.