I don't know, but the thing that really hits me with this video is the idea of books for barter. There is a lot of other evocative imagery and ideas as well, though.http://www.youtube.com/watch?feature=player_embedded&v=FrHkKXFRbCI
I've been reading this absolutely fascinating book "Debt: The 5000 first years" by David Graeber, that examines debt, guilt, obligation, barter, economy, currency... I could totally see the Barter Books store as a local hardhold, the hardholder knows the value of pre-apocalyptic knowledge and thus will pay for any books presented to him.
Since a book can always be spent as tribute and trade with the hardholder, it's become an established currency among the locals. There is this advanced economy of debt, obligation and control through books. The library is at the same time a bank. Valuable books have blood on them. Do you just use books for currency, or do you read them as well? Makes a huge difference.