Exactly. Of course, there are some details that might cause problems. A landlord might expect more headaches and confusion from someone subletting the place, a

Exactly. Of course, there are some details that might cause problems. A landlord might expect more headaches and confusion from someone subletting the place, and may want to raise the rent to compensate. Also, just because it's inefficient doesn't mean that it's easy to solve. Copyright is obviously inefficient, but not easy to solve.