Without turning this into another tipping thread, it's bad enough that in the states we have the tipping culture but it's downright insulting when they choose the amount an include the tip on the bill (I understand when it's a big party though) I always tell them to take it off and often will mention to a manager if I see one that the concept is insulting to both their customers and their staff, because if their staff is any good they'll likely receive the same or bigger tip.