[wrenky]

Customers dont have to guess, just pay the 15% and leave. Thats just the standard.

If a company chooses to pay more, their prices go up and they cant compete. Even though its just shifting the cost from a hidden to a declared one, its enough where restaurants struggle and either abandon the model or go out of business. Its an industry problem that needs to be fixed at that level, you cant just say "Go out of business, Done!" as thats not a realistic solution.