Look a free market is simple, you trade 1 item for another, you want the other item more than yours, and the counterparty wants your item more than his, so when the trade is complete, you are both better off.
How is that not collaboration?
The trading you describe is barter, not a sophisticated monetary market of the kind generally discussed. I agree that barter is better, but it is impractical on a global scale.
Item one: My shoes.
Item two: A bitcoin.
How is this impractical on a global scale. How is this not collaboration.