It is really bizarre. I worked at a wannabe-Chili's restaurant in the Midwest for a while. The most unexpected thing I learned was that college-aged couples understood the struggle. Different people on different occasions, they'd be super easy-going, and they tipped me $20 on a bill of like $18.

This made such a huge difference when I was making literally $2.13 an hour.

Bigger families with kids or stuffy "business meeting " people usually ran you ragged and tipped like garbage, also while leaving the surrounding area absolutely demolished after camping around long after their meal.