Well, I found a strange exploit (that I haven't seen yet on the forum, anyway). I don't know how repeatable it is, maybe someone could try it out and find out?
I sent a sim to France for a variety of tasks. She set up her tent in the market place, in the room next to the bookshop. She went by to read a couple of books from the nearby bookshelves. Rather than finding a chair, she went into her nearby tent to read them. After a few books, I noticed that they were appearing in her inventory.
Sure enough, when I returned home, the books were still in my inventory, ready to be sold for a tidy profit.