I didn't work in food service but I did work a service job (supervising children, teaching robotics, and hosting birthday parties for kids) in high school. I did not manage to save any of the money I made, but I definitely learned a lot from the experience. Namely: most people have no respect for service workers, and some people seem to have active contempt for them. Quite unpleasant. I don't think high schoolers should have to work for a living, but then again I don't think adults should either. However, I do think the experience of working service jobs is one that more people should have.