I tip if my waiter is nice and fills my drink up and isnt a pest, i will tip 20% or better but if the waiter thanks that they should get a tip just because and gives bad service oh no they will not get a tip of 20% maybe like 5%. Its your job to serve no one made you take that job of say $2.50 an hour and tips? you want a tip you do the job and you will get one 100% of the time and i am not saying you should kiss peoples a$$, if the place is busy and i can see that i understand slow service but not no service.
some not all people in the restraunt service excpect a tip as soon as you sit down at there table, i eat at chillis alot and they know me there and still if i get good SVC a good TIP bad SVC little TIP.
Oh well its like alot of people say you wont know how they fill until you walk a mile in there shoes. a friend of mine says if most people that were rude to retail and restraunt people every worked in there industry wouldnt be. oh well remember you still have a job and you wake up every morning and are alive.