Fry's Electronics Refused to accept a return within policy guidelines Roseville, California

I tried to return a NetGear DSL modem open box 13 days after I bought it. It was returned in perfect working and cosmetic condition with all accessories well within the 30 day period. Fry's customer service refused to issue me a refund on the ground that they though that I had tampered with the serial number. The corner of the serial number (and MAC address) sticker had peeled off a little bit. I'm not sure if it was caused by the previous buyer or if from the heat generated by the modem but I certainly did not do it. The serial number matches the one on the box but they still have accused me of trying to defraud them. These people are clowns. They sold me a DSL modem with the serial number sticker corner peeled up and now they won't take it back. I can understand trying to take preventive measures to reduce return fraud but making this sort of accusation just because the serial number sticker corner is slightly peeled (especially since I bought it as an open box item) I think is a bit ridiculous. Fortunately I paid with my credit card and it is currently in the dispute process.