Since the topic is Dell, I noticed a while ago that the major computer brands (Dell, HP, Lenovo, maybe Asus does it too) will have different SKUs for each retail outlet. You could find a computer at two stores with the same specs and same chassis, but because the model number is different by one letter it's excluded from the store's price matching.

But it's also no secret that computers are a loss-leader for retailers that want you to buy additional higher margin products while you're there.