you know how you will see things on clearance? Those are items that didn't sell well (exempting holiday related stuff) and when that contract is renegotiated it will be for a smaller quantity or the product will be dropped. The generic milk at my store got dropped, i talked to the manager and it was because they were losing too much of it. Sticking with the milk thing, we could pretend that the dairy farmer is on slim margins (pays out and gets paid almost the same amount with just a little bit of profit); and fuel, feed (fuel, seed, fertilizer), upkeep (steel, labor, manufactured goods) market exposure dictate what they pay out. He has pretty much a required price he has to sell at, or he stops the operation. Bottling the milk has larger margins, but those companies would refuse to take a hit, so it is basically pay the price or don't buy the product in the future.