You have seen, during yard sale season, the forlorn little collections of articles piled at the roadside with a crude sign propped against them: FREE. These are the unsold remainders of the long day's effort at household commerce. They are the lowest, poorest bottom of the unwanted. You might find a ratty recliner that doesen't recline (or unrecliine); an old vacuum tube radio that was last heard from in 1957; a single bicycle tire, flat; a box of old National Geographics, mildewed. Days will pass, the rain will fall. and the Free pile will sit there, undiminished. At last the would-be-seller will give up and cart the articles off to the dump. You can't give this stuff away.
You can't give it away, but it has always seemed to me to be a mistake to try to dispose of the useless by taking it out of the market entirely. After all, how much more abject is the junk in the Free pile than the junk that has been successfully sold around and beside it? Not much more, I suggest. The astute seller, rather than trying to give away his remnants, would put up a sign advertising them for, say, one dollar; he would assign them not much value, but value nonetheless. My guess is, they'd move. Unaccountably, people will accept for a price what they disdain for nothing. In the sea of the Free pile and the yard sale, the ship of Supply and Demand sails in to shoal waters.