Or, if it's not privately owned, look for the corporate site and report the little bastard

My honey does that, since it's rather illegal to punch the varmints...
Let's see, he reported people to corporate Sears when they wouldn't honor an agreement to repair some jewelry we just bought there like, the day before. We got a phone call the next day from one of the vice presidents personally asking what they could do to make it right.
Reported a doofus cashier at a video rental place who tried to charge him for being late for a video when my guy had just, half an hour earlier, handed them in to the girl. She had laid it on the counter instead of putting it in the right bin under the counter.
Most people think doing that has no effect but when you make the complaint and tell the exact store, it does get sent to the manager of that place. I recommend, that if you can still remember the guys name, call the store and ask for the manager, and tell him what happened. But don't use your own phone. Alot of people, instead of changing the way they act, get vinidictive.