Do you think tipping at a restaurant is necessary? Why or why not?

So does wait staff in North America. My daughter is a waitress at a chain restaurant, and sometimes she doesn't even make minimum wages after tips, if its a slow night or if she gets a few really cheap customers. I raised my kids waitingtables, and I can tell you, sometimes you just want to spit in people's drinks. I have been left $5 on a %150 bill before, and it wasn't because I didn't give good service. I made the dishwasher change his shirt, wash his hands and come bus tables for me in order to ensure prompt service to that party of 10 and my other tables. he got my whole tip, plus. luckily today, my daughter made $180 before her 5% tip-out so she has enough to buy groceries for her husband and kids this week.