No voluntary tip, it's a mandatory service charge in most European nations and they add it into the bill.

(And then I've seen a waiter lie when asked by an American tourist if there was a service charge added or whether a tip was expected. I had to show the man and his wife on the menu where it noted [in Dutch] that the service charge was added. The waiter was angry with me, of course. However, as noted above, there are bad apples in all cultures, and for the most part my experience with the Dutch has been very positive. Now, if we could just do something about those small beer glasses . . . )