I think it boils down to "how does the company advertise pay to the employee?" Those restaurants are not advertising minimum wage + tips, or even just minimum

I think it boils down to "how does the company advertise pay to the employee?" Those restaurants are not advertising minimum wage + tips, or even just minimum wage. They're advertising $4 + tips. Amazon should similarly advertise whatever it's guaranteed to pay itself + tips. Then it's transparent and there's no confusion.