I mentioned this on TDR also. B&N was affected by Hurricane Sandy. Stores closed because of no electricity at the beginning on their holiday reporting period. People are still recovering and cleaning up. Hundreds of thousands still unable to return home.
You're not thinking of books while living in temporary housing. No one feels like packing them back up again in a few months. Changes in FEMA policies are reducing purchases of non essential items.
While this doesn't explain all their losses it may explain some of them.