Yes, that's the classic description of a future commodity contract.
However, the speculator does not actually make the market for the produce being delivered.
Farmer A in jan. wants to sell a bushel of wheat for $1. he hasn't harvested yet until say march. (yea, don't know off the top of my head the seasonal as I haven't done wheat in years, so just an example)
Baker B agrees to buy a bushel of W from A for $1 in march so he can make profit selling bread. The underlying physical commodity price doesn't change for those two guys in march. Back in the day, Farmer A has a terrible crop and can't come up with the wheat. Since it was an agreement to pay if received, the contract expires worthless. Normally there was no deposit given basically because of the uncertainty of the future. Both are out of luck.
But then speculation on the contracts themselves opened to all including the growers and buyers themselves which gave farmers the ability to 'leverage' their commodity even if they don't produce anything.
So, it went from two guys agreeing with paying only if one of them produces something at a certain time with basically no strings.
You pay me for my apples if I bring them to you, but you don't owe me anything I don't show up. Simple.
It was the introduction of open speculating on contracts themselves and not the underlying commodity that I contend makes a false market that doesn't really move commodities in the real world. The markets basically took the concept of currency trading and created options on commodities. The middleman is only for separate profit from the real market. That's my contention.
Weird as it is.
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