[Porsche-O-Phile]

For sit-down type service I’ll tip based on level of service (typically around 15% for decent, 20% for good, higher for great and less or nothing for poor or terrible).

I absolutely do not / will not “add a tip” for counter service places. That’s called a job and the staff is getting a paycheck for it. There’s no service involved beyond making a sandwich or coffee and / or punching some keys on a register. “Service” is something above and beyond the minimum level of effort by the business to justify charging anything at all - it’s not doing one’s job. If one goes “above and beyond” then they get special recognition for it. That’s the whole point of a tip.