I tip cocktail waitress $1 per drink because I requested the service.

If a bar machine spits out a voucher saying the casino owes me a drink. I do not tip for that drink as the establishment told me that I am owed it.

I tip $5 for for a single server delivered meal. Whether that meal costs $5 or $50.

I tip $10 per person in a multi server environment. I don't care how much the meal costs.

I only tip on machine pays if I feel I am getting something out of it. Used to do $20 but I was scorned too many times. I am now scorned but save the $20.

I tip for things like haircuts with my regular barber 100%, furniture movers, things where people are really doing something for me some would say excessively.