You're right about the recycling, of course. But, a lot of that paper goes into reports and stuff; those would have to be filed and thus can't be recycled. Otherwise what's the point in keeping files?

Now paper-mill ships occurred to me as well -- a thought which I dismissed almost immediately. Having a flying fuel-refinery is one thing and it's already a stretch for it to conveniently have survived the attack; having a paper-mill would be pushing it. ;)