It is customary to tip most people who do stuff for you. Waiters and waitresses are an obvious example, but you’re also supposed to tip doormen, valets, maids, delivery folks (pizza, etc.), and more. Since tipping is customary in these situations, you should do it. People in most of these jobs are grossly underpaid, wage wise, since their wage structure assumes that tips will make up the difference. In many cases, the federal and state minimum wage laws do not apply (or, at least, do not apply in full) to people who can be reasonably expected to receive tips.
Having said that, I think we should stop making tipping customary. It’s an annoying, largely useless tradition. When I pay the bill at a restaurant, I have paid for the food, the wages of those who cooked it, and the wages of those who served it. The way it should work is the actual, list price of restaurant food should be increased (say, 15 percent), servers’ wages should be increased to a fair amount for the job they do (minimum wage or higher), and the whole tipping process should dissolve into oblivion. Good service is a reasonable expectation, and the way to punish bad service should be to report it to the manager (so the server, if bad service is a pattern, can be terminated). If we really don’t want to let go of the silly tradition, then permit tipping in cases of exceptional service (say, a going rate of 5 percent) but it should never be expected or necessary.
