How about this angle. Your paying a girl to be a waitress. She happens to have a nice set of teeth. Daily customers want to have their picture taken with her. So she makes an extra twenty bucks per snapshot at your restaurant.
Is that okay?
Somewhere there's going to be a conflict in this. Either someone's going to want their cut and think they deserve a percentage. Plus the college academic or athletic scholarship is paying the athlete to be there so it's already on their dime. Athletes on the scholarship are on a scholarship for a reason and there's an academic reason and there's an athletic reason they're already being paid to be there. That money has the biggest skin in the game.