$400 tab for tying up a table for 2 hours seems legit to me. It's not like they were sitting drinking free water for the 2nd half of their dinner. If the waiter had 4 tables and they were all tied up for 2 hours and he "only" made $400 that night, it seems pretty good to me. But waiter likely had more tables, and after the 2 hours were up, he at least turned them all once. When I read this thread, some of the opinions make me think that the tip should be based on the time you spend there.
That'd be fine with me, as I can ring up a big tab in a short time.
