Not since the age-old question of "Who is the EMPLOYEES MUST WASH HANDS sign in bathrooms for?" have so many people been miffed in restaurants. More and more restaurants, particularly in NYC, are showing a "Recommended Gratuity" chart on the bottom of their checks. For instance, if you bill was $50, the bottom of your receipt would read 15% = $7.50, 20% = 10.00 and so on.
I love this, don't you? There's no math involved and thus no chance of incorrect math (unless you make one in the actual counting of physical money).
Some folks have complained to me that it feels pushy and presumptuous of waitstaff to "point out" what's expected. "Isn't it MY choice what to tip them?" I've heard more than one person inquire.
First, this is the restaurant's choice to put this chart on your check, not your waiter's/waitress'. It also helps serve as a friendly reminder to our international guests who may not know how tipping is conducted in the states.
Secondly, it's only "Recommended" - you can always tip what you want. Bad service is bad service, and the tip should reflect that, but excellent service is priceless and must always be recognized appropriately.
If you're ever in doubt, here's a handy website called "The Original Tipping Page." http://www.tipping.org/tips/us.html