Earlier quoted context omitted.
If you want to claim to be principled about this then you should inform the waitstaff at the start of the interaction that you don't intend to tip. The price they ask has expectation of tip built in implicitly - failing to disclose that you won't tip is therefore a lie of omission. I hope you're not that sort of person.
2 thoughts. #1 - I feel you are assuming requirements about the optionality of tipping. The gratuity is optional for whatever reason, regardless of social expectations. So in my opinion one can be moral and ethical without disclosing why they don't tip. #2 - I waited tables, and a very good waiter once told me that he gives every table the same service whether they do or don't tip, and no matter how much they tip. I…
Likewise there is an expectation of good service from waitstaff, but they're not obligated to give good service. They too have the option of giving better or worse service at their discretion. So if a server wants to give everyone equal service that's their right. But if I want to develop a reputation as a good tipper to get my service prioritized over GP by servers who differentiate then that's ok too, and rational I think.