This was odd to think about as there was a person who tipped at restaurants which isn’t uncommon where you would give say 10% of the bill to the staff. In this case though, he actually gave extra tips directly to the staff in the form of cash where they should be getting both. His reason was by giving more they will then give him better service the next time they see him versus potentially giving bad service.
That is a little odd to think about as one should be trying to treat customers the same correct? Imagine paying more for a product at a retail store in hopes to get a worker that may be happy to see you as an example. It would make me think that would be an example of things like a tip going too far if people expect that in order to provide a standard pleasant experience for the customer.
I can understand one being more enthusiastic, but not the difference between spitting or not spitting in someone’s food.