That's why they sold it with a game instead of just the console.
The original xbox was sold, then returned (maybe it was defective, maybe little johnny just didn't want it). Microsoft tested it, repaired it if necessary, but was then unable to sell it as new. To get around that little 'law' problem, they made it a bundle, they threw in a game. Different SKU means different product, which means it can be sold as 'new' again. It's actually quite common in the gaming industry. When you take a loss on the hardware, you really don't want to throw the systems out if you don't have to.
I also believe that some (not all) of the forza bundles were returned in this manner and MS is trying to depleate their stock.