marco:

Have you ever seen a book or magazine that said something along the lines of, “If you received this book without a cover, the author hasn’t been paid for his work”? That’s because book and magazine publishers have a similar arrangement with their vendors, except that the publishers often required in the past (not sure if it’s still true) that the store tear off and send back each credited item’s cover before throwing away the rest.

I’ve always wondered about that.  Now, thanks to Marco, I know.