You grow wheat. You want to make sure that you can get $X for your wheat in 6 months and you are willing to risk the upside of a wheat shortage for protection against the downside of a wheat glut. Your counterparty makes bread. They're willing to lock in a price of $X now for wheat delivered in 6 months at the inverse cost of your reasoning. You've both hedged. The world is better because I can buy bread made from wheat in 6 months at a reasonable price. Traders and Wall Street came along and perverted this, but it is still a primary purpose of the market at its bedrock. If the bakers and the farmers disappear, there is no wheat market for the traders to pervert. It is the foundational hedger that the prohibition protects.
Compare: you trade crypto. You want to sell your crypto for dollars. Later, you want to buy your crypto for dollars. When the hell does anyone else care about your crypto? Why would we care about the integrity of price discovery in the crypto market when it has (or should have) no impact on the real world outside of your economic gains/losses? If we don't care about price discovery and its integrity, we have no need for the prohibition.