Twenty percent is industry standard. This is especially the case at higher end restaurants. I've been waiting tables throughout graduate school, and in various places throughout the country for ten years. Eighteen percent is what most restaurants will apply to autogratuity situations (big parties, specials, coupons).
If I get around twenty percent, I'm fine with it, even if it's low. But if I do great job, develop a real rapport with the table, make tactful and effective recommendations, I often get 25 to 30 percent.
Anything lower than 18% communicates 1) that the server did unacceptable job 2) you are cheap. You may not agree with it; but that's what your tip communicates. If you return to that same restaurant, you can probably expect to get the service you previously paid for (i.e. you've made yourself a low priority). If you don't like tipping that much, order in.
Part of the reason for this is not only do servers get paid low hourly wage (around 2 bucks, except on the left coast), typically restaurants, esp. higher end one, only are open for four or five hours. So a server must make their living wage between those hours, even if they have other duties that can take an hour or two (opening, closing, sidework). And trust me, most servers have a second job or go to school, because it is difficult to make a living-wage exclusively waiting tables five days a week.
To put it in perspective, when I go out to eat, as a person in the industry, I tip 30%, unless I receive horrible service. And I live right at the poverty line.
Last edited by Pseudofool; 02-08-2013 at 08:58 AM..