It depends on the type of book. For fiction this is definitely true. For textbooks and technical books, there is a massive used market with high resale prices,

It depends on the type of book. For fiction this is definitely true. For textbooks and technical books, there is a massive used market with high resale prices, which is more what I was thinking of. I suspect a lot of these vendors simply won't jump on the bandwagon without some kind of reassurance.