The anglocentrism is pretty strong there. 'America is so weirdly and determinedly backwards...'?? Or maybe just different?
I'm sure there are servers in the UK who would love to have the chance to make what a waiter makes in a decent restaurant in the average American city. University students on J1 visas can make enough waiting tables to set them up for the year.
Nobody is twirling and dancing. What a really odd thing to say. They're schlepping your food to you, telling you about the daily specials, they've studied the menu earlier and can answer your questions about ingredients, substitutions, etc. If you're not happy with the service, you don't have to tip. But it would need to be terrible service on every level to do that, something like sneezing in your food, losing their false teeth in your salad..
There's some weird form of reverse snobbery being expressed here. Are you not comfortable with people providing services for money?
Restaurants can add a service charge to the bill for parties over a certain number, at their discretion. It reflects having bus staff tied up at a bigger table, perhaps moving tables together, and having one waiter tied up with one large party means he can't serve his usual number of tables. It also reflects a large amount of cooking and plating all at the same time back in the kitchen.
The service charge goes to the restaurant, not the waiter, for tax purposes. The waiter is still expected by the IRS to make the gratuity income and will be expected to pay the estimated income even if the customers have waltzed out without tipping.