So the customer that buys the PS3 (we'll stick with the PS3 since this is VGChartz) from Walmart has to BUY an ADDITIONAL $433 worth of items just so WalMart can BREAK EVEN on this promo/transaction.
That is a very big assumption and does not make too much business sense UNLESS there are other factors (such as manufacturer incentives).
Please feel free to add if there is anything I may have missed.