This topic greatly angers me. I hate tipping so much that I consistently avoid places where I have to do it. I hate spending a week's worth of grocery money on a single night just to be able to have a sit down meal and a drink with my wife.
I think that any "tipping" that is expected should instead be rolled into the cost of the service before that service is rendered so that consumers can make the best choices (this has been mentioned here many times).
I think that empathy and the idea that it is "our responsibility to make sure the wait staff gets paid a livable wage" is EXACTLY what has drove us to the horrible situation we have today, and continues to drive the "standard" tip rate higher and higher. Unfortunately that is the view of most of the people in this topic. Its no wonder the US tipping system is so out of control.
Now don't misunderstand me: I totally believe that the wait staff should make a livable wage -- just not that it is the customer's responsibility to make sure that happens on a meal-to-meal basis. It is the responsibility of the worker, and the business owner if the owner wants to have skilled servers. The power of the market will take care of the rest. For example, consider if everyone in the US suddenly stopped tipping: wait staff would naturally move to restaurants that payed higher wages. In turn, if restaurants wanted the best service people in order to attract more/better consumers, they would have to pay more to the wait staff. And as workers, the wait staff should choose jobs that pay them an appropriate amount, and don't take jobs that don't. This would produce more certainty/consistency in weekly pay and transparency in the cost of the service. If a wait staff job does not provide enough money, then go to college and get a different job.
Why is this SUCH A BIG DEAL for wait staff? What about the grocery store? Do you tip the cashier for helping you pay for your groceries? Do you tip the workers for stocking the shelves? Do you tip the truck drivers for delivering the groceries to the store? No, you don't, because that is all part of running the business. As it should be part of running the restaurant -- it is total nonsense to separately tip the wait staff. And the only reason it continues is because the social pressure to tip (no one wants to be labeled as cheap or as a jackass) is preventing the market from smoothing everything out and allowing restaurant owners to get away with paying low wages.
I know that the social pressures involved are much too large for this to fix itself anytime soon, and I don't expect my opinions to elicit positive responses. Just as with anything we buy, we are supporting the broken tipping system by visiting places where tipping is the norm. Just as I don't own a car and don't eat meat/dairy, I'll happily continue avoiding services that require tips.