Walmart strategy:
purchase in advance, when bestbuy/circuit city/staples/wherever opens at 6am, be in line at walmart with your bag of returns. Go to the return desk (I'd guess there will be no line there at that time), return, repurchase with price match. Suggest to them that they save their time - even if the store you were PM'ing to had none of the loss leaders left on the shelf, the items would still be in people's carts and thus, technically still in stock 🙂
However, and please correct me if I'm wrong, model numbers at Walmart are often verrrry similar, just an added letter. As someone explained in some other thread here, the difference that little letter made at the end meant that the name brand company that produced the (laptop in the case someone posted about) item completely switched components inside, rather than using name brand components (ie, instead of maxtor or western digital for the hard drive, the hard drive was made in some company from Shanghai; similarly none of the other components were made by recognizable manufacturers.)