Like reducing the amount of water on the floor would be turning off the tap. Absorbing the amount of water on the floor is when you mop it up.
To reduce volatility you would need to actually stabilize the supply of onions.
What futures do is allow traders to shift risk from the future to the present. By pricing that risk, it's possible for people who depend on onions to pay a little more now in exchange for a guarantee about the future.
It's not magically going to make onions less volatile (although high risk prices can spur investment which might) but it can reduce disruptions caused by volatility.
The classic example of this is futures on jet fuel which allow airlines to weather random wars in the middle east, OPEC shenanigans, etc. Ticket prices are higher this way, but the existential threat of being forced to cancel a bunch of flights is gone.
If there is a supply shortage prices will rise; no amount of futures trading can create resources out of thin air.
I’ll keep paying though.
Traders are often happy to take the other side of that trade because they can trade against many counterparties, collect a small premium from each one, and try to ensure their counterparties won’t all fail in a correlated way.
Would you rather have net profits of 20, -10, 15, -5, -10, 25, -5 year over year, or profits of 4, 4, 4, 5, 4, 5, 5?
Your hung up on money, everyone is trying to explain that the exact same money is better when it is predictable versus erratic.
Yes, it is about the money.
And rarely is done by farmers.
And consumers neither lock in margins nor run a business because consumers buy at retail…
Ok charitably, maybe you use “consumer” in a special sense of businesses that consume raw materials such as owners of onion ring factories. In those cases, future prices (as opposed futures prices) are typically negotiated directly into contracts with producers of those commodities…and how many of those are in this thread?
In the vast majority of cases, futures are traded speculatively and physical delivery of goods and chattles is an extreme exception.
To the farmer, futures mean no risk of having to sell when prices are low. To the buyer, futures mean no risk of having to buy when prices are high.
The farmer also gives up the chance of selling when prices are high, and the buyer gives up the chance of buying when prices are low.
The transfers go both ways, which is the magic.