Yeah me and my cousin when to Microcenter a couple of days ago to get him a GTX 260 and I asked the guy what kind of ATI cards do you got? He was like "What are you doing with them gaming?" I said yes and he replies "Well go with nvidia they handle games much better.." I asked him why and he just walked off and helped someone else...
If that doesn't work.. slash his tires and paint ATI in red on his windshield.
Salespeople like that really piss me off.