It undermines the norm that employees should be paid for their labor regardless of what the customer thinks --- that they can be fired of course but not underpaid for the labor already performed

It undermines the norm that businesses should pay their damn taxes.

To wit, we have been able to put off discussing the non-profitability of restaurants for far too long until now. Remember, it is quite arguable that Baumol's cost disease = "progress", not by definition, but by bi-implication.