In economics, there are the idea of pure advantage and comparative advantage which encourage specialization and trade. This isn't for control, but for mutual benefit through trade. There's also an old adage that when goods do not cross borders, armies do. Wat is the health of the State, and trade promotes peace and prosperity outside the State, so absent regulations, taxes, and tariffs, I doubt the powers-that-should-not-be like it very much.
I looked into local auction sites before I bought the friend-shaped car from an acquaintance. I haven't tried it for other stuff, and I don't much want extra stuff, just specific essentials.