Not even really zero-sum, because selling it to the person valuing it the most (to whom it is most useful) does create value.
But it's not as satisfying as making something that never existed before.
Balls. Go to a commodity exchange and you know how you find the price? The last price paid at auction.
Sometimes the negotiation is disguised, using an order book or dealer system.
But sometimes they even explicitly run a call auction.
All Wall Street is is a continuous auction house.
All Supply/Demand is is a continuous auction.
Not even really zero-sum, because selling it to the person valuing it the most (to whom it is most useful) does create value.
But it's not as satisfying as making something that never existed before.