Fry's Electronics rebates seem to be one company giving the rebates for multiple devices or items (Printer, CD player, hard drive, etc)
The fine print states you can only get one rebate from X company a year. X is not the manufacturer of the device or item, its the company that gives you the rebate. Its another form of marketing. They market the product with a rebate, you buy it, then find out you cannot get the rebate because of the last product you bought. You keep the product because you needed it in the first place. The marketing/rebate company has done its job, they did not lose the rebate money, and it gets its paycheck from HP or Samsung or whomever.
Cool huh?