And tip on what was served if items have been comped and the bill is lower than it otherwise would have been. Somebody still had to prepare and serve the food. One of my more embarrassing restaurant experiences here was going with some music biz guy to a place a good friend chefed at. We must have had over $600 of food and drinks sent out with the wait staff instructed to treat us like family and the guy (oh so magnanimously insisting on charging to a corporate card) dropped $15 on a $100 bill that barely covered appetizers. I ended up sneaking back in to make up the balance.
yeah, i hate comping food for people who are "friends" of the boss, b/c they very rarely tip on it. the kicker is that the friends are usually pretty damn rich themselves, so it's like let's give free things to the rich and make the poor suffer . . . .
only exception to this is that, when at a bar, it's not stylish to tip on free drinks. rather, you should wait until the next round and then leave roughly 3x what you'd normally tip . . . .
suppose we have a bar that serves $5 beers
suppose, too, that bartender likes you and always gives you $3 beer
suppose, last, that bartender gives you a beer free of charge
you should smile and accept the free beer without tipping on that beer
however, when the next beer is served at $3, you should leave a $6 tip