That’s not the point I was making though. If the servers are tipped less due to this policy (the other person’s claim) and make less money, they’re likely to quit because serving has extremely high turnover anyway
However -
Servers regularly are tipped above “target percentages.” This is a fact - especially once you consider places with low cost-per-plate (diners etc). If you pay them 15% of total sales or whatever you’re essentially capping tips at 15%, lowering their wages.