I don't know why it is, but every used book store I've ever gone to has a set of law books and law school text books. And, when you talk to the owner of the store he will always gripe about how he got stuck with them, can't get rid of them, and say he'll give you a great deal if you'll just take them off his hands. Then he quotes you a ridiculous price for out of date books which you'd never use.
I discovered a used book store yesterday and, sure enough, in a far back corner these books were up on the wall. Of course, the law school books are useless and the out of date "modern" statute books won't really do me any good. However, that black book on the far left is a 1930 Virginia Code (all in one book). I would be interested in having that. However, when I approached the store keep he refused to quote a price for that book alone. Anyone who wants it is going to have to buy every single Virginia statute book they have.
As you might imagine, the books are still sitting there on the shelf.