Stupid People Make Me Cry

Even when I'm NOT on courtesy, the crazy ass people seem to just seek me out! Literally five minutes before the end of my shift. I'm just done cleaning up my register and this douchetard comes in with an EMPTY bag of chips saying he wants a refund because he didn't like them. He didn't like the now EMPTY bag of chips. I'm looking at the bag and he must be able to see the 'who the frak are you kidding' look on my face because when I ask if he had the receipt and he says it's stupid to expect people to keep their receipts, why would someone do that. I very pointedly remind him that he's there for an exchange, but I can see that this douchetard doesn't get it. He starts getting all angry and starts swearing and yelling and wants to see the manager, I remind him the store is closing in an hour, the managers don't stay until midnight, only the front end is open at that hour. He keeps going on and swearing. At that point I simply give him the store number and tell him to ask for the manager tomorrow. I'm no longer dealing with his crazy ass. Losing his freaking mind over a 2 dollar bag of chips. He had to be either drunk or stoned. Douchetard.