I have recently been receiving number of visits from "academic book buyers" that are looking to buy books that I no longer want. It is never stated outright but they seem to be looking mainly for evaluation copies of textbooks. At least 2 of the cards that I have been given indicate that they are "recycling" the books, although what this means is not clear.
Are these book buyers benefitting or exploiting academia?
There are good chances that they are selling the books back to students. Given the price of academic books, this is is the most profitable way of "recycling" a book.