This is the kind of thing that really gets to the heart of the OP. It's not complaining about tipping in general and it's not schmidting on the most vulnerable in our society. It's exactly this.
FWIW: One of the more well-known bakeries on the West Bank ... when you buy items to go over the counter and pay with a card, the machine tries to show you suggested tips.
The employees there take it upon themselves to hurriedly swipe away from that screen so that the customer doesn't have to deal with it. And they do it consistently.