"But I've done it before."
This is one of my all time favorite cop-out attempt from people trying to get their way. This has several benefits. One, it is usually not proveable in the negative, i.e., we can't PROVE that you didn't get your way. Moreover, calling your bluff basically means that I'm calling you a liar, which is a rather dicey proposition - one that can get REAL ugly REAL fast.
Polite is the only way to deal with these. Polite and basically quote the rules verbatim. I'm good at this.
This guy comes in. He's got one of those remote control boats. Those things never work — BECAUSE IT COST $14 AND IT IS MADE IN CHINA PEOPLE! What do you expect? If you want good stuff, you've got to go to Sharper Image!
Anyway. He doesn't have the receipt. I tell him he can get store credit and that I need his drivers license.
He goes "I'd like to get cash if I can." I tell him "I'm sorry sir, but without your receipt, I can't give you cash back on this item."
Him: "Well, I've done it before."
Me: "Sir, it is a company policy that without your receipt, we give you a store credit for the item."
Him: "Well, I've done it before. I'm from Ohio."
Me: "Sir, without the receipt, you're only going to be able to get a credit."
Him: "Well, I want to talk to a manager. I've gotten cash before."
The manager on duty happened to be nearby. I go tell him what happened. The first thing he said was "This ain't Ohio."
One of the supervisors came up there and told him he could get credit or nothing.
He took the credit and left.
I had another guy Sunday night return an expensive video game for a cheaper one. He didn't have a receipt, so I put the balance due on a shop card. He balked at that, saying "I don't live here."
I shot right back at him: "Sir, there's a Wal-Mart in every state in the country!"
He shut up and left too!