I dread the day I have to eat at US restaurants, or even get something delivered. Part of the reason is cultural: I’ve never lived in a country where a tip is mandatory and you’ll be called out if you don’t. The other reason being it involves a degree of social pressure and shame, if one doesn’t tip enough. Both don’t sit well with me. But I can attest that if I’m forced to tip, I’ll not return to that establishment.
Also, tipping is a monument to human stupidity. Apparently, people would rather pay €10 + 20% tip than €12 with no tip, because the former feels cheaper, even though it's a stupid way to organize pricing.