Anecdata, but I go to Taco Bell way more often than I should. There’s no tipping culture at Taco Bell, but the staff, at least at the one near my house, are always very nice to me and as far as I can tell my food is made with a sufficient amount of care.

When I do go to a restaurant that has tipping, people are usually nice to me as well, but I don’t feel like they’re really any nicer or better at their job than my local Taco Bell workers.