I would have done more then kicked him in the balls.
I have heard things like that so much about the Xbox,mine was in Blockbusters,two guys were standing there with 3 ps2 to rent,and the clerk goes,once the Xbox get here say bye bye to the ps2,i started laughing as hard as i could,just to make sure he heard me.
One thing that makes me laugh about your story is these guys are ment to be selling stuff,not making people change there minds,and put there products back,how stupid is that.
Also i think i am going to go back in there and make him feel a fool,start throwing all the gt3 sold on the first day,stuff like that.