If a state or local government wants to forbid tipping it doesn’t have to be this complicated. Pass a law that says it’s forbidden, that credit card merchants and POS merchants must disable tipping functionality, and for cash tips up a hotline & fees for merchants that solicit them.

Tipping is only a thing because we’ve normalized it. If you pass a law against it, it’s no longer normal, and customers will mostly stop giving them, even without highly intrusive enforcement mechanisms.

The real challenge is getting a government to want to forbid it, because people who receive tips care about them a lot while those that don’t, don’t. Until you solve that nothing else matters. Maybe tipping will go so far that the balance shifts.