I mainly tip for social pressure, and custom.

• I’ve always considered it unfair because even if you think the customer is responsible for the income of waiting staff, what about the rest of the crew? But that’s the world we live in and it’s also unfair to individuals to make a point of stiffing them
• Also, why is it reasonable that waitstaff get a larger tip simply based on how expensive the food is?
• tipping for drinks is the worst. Not just the highest percentage, but usually to get any service. It’s rarely good service and it rarely improves

That being said, I’m sticking with the traditional amounts, even if I need to fumble with buttons. And I’m not tipping in all these new places that never had that expectation. And I really don’t care about the social pressure anymore.

A couple places made it difficult to enter a traditional tip to the point where I decided 0% was easier.