Gratuity's are include at most better places. In SoCal, around 18 to 20% (in Europe it's always included). Even though, that $40 was rather uncool. A tip required may also depend on the size of the party. Table servers have a tough time dealing with drunks, guys trying to impress their dates/friends, just plain snobs (just think of TA in a better eating establishment) other all around A-holes. You really have to love taking crap from all sorts of people, including the managers and some chiefs.