the core of the problem is this: Prices are arbitrarily assigned with no consideration of supply or demand. 'tis why free market societies have a better track record than, let's say, communism.
and HEY, if only we weren't buying and selling goods to NPCs, where they come from and disappear into thin air, but rather bought and sold to each other, you know, players. Then and only then would the actual value of items emerge.