Ok, What is the risk of Fisherman ? Big. And if he have some future contracts - that risk is even bigger.
What is the risk of OilDriller ? Big enough. In that case, future contracts are somehow lowers the risk.
What is a risk of gold mining company - there is some risk. Actually futures on that marked, increases the risk taken.
What is risk of Miner contracter ? - No any risk. All risk lies on shoulder of contract buyer.
Get my point ?
Please tell me English is not your first language. I don't mean to be rude, but I'm not sure anyone really gets your point. I'm not sure you really understand futures contracts, as you seem to imply they increase the risk of the producer. That's the exact opposite of what they are for. Futures are hedges against unexpected changes in the market. The farmer, miner, or oil company will lock in a price today for the products they will produce and deliver over time. Effectively they win when the market price would have gone down after they lock in their price, and lose if it went up. It doesn't imply that they lack any faith in their product or its viability, it's just they need predictable cash flow in order to meet their liabilities such as payments on debt and wages for employees.
A mining contract is similar to a futures contract. The bitcoin miner has to put up capital to get the venture online and wants to guarantee a level of cash flow that will make them a profit. Let's say it costs $10,000 and a lot of time to put 10ghash online. The miner could of course assume all the risk and all the reward of the venture and not engage in any contracts. But there are limits to the amount of capital one can put into a venture, and limits on the amount of risk one is willing to take, regardless of how optimistic they are about the future. Once they have had their fill of risk, an option to keep expanding is to sell mining contracts at a profit.
It sounds like you are trying to say saying that in a contractual agreement between two businesses, both parties should take equal risk, so if the buyer of the contract loses out on the deal then the contractor should lose out too. While that's an attractive option for the buyer it makes no sense for the seller. The seller in this case gets no upside benefit should bitcoins go to $100, they just get the contracted price. If they get no upside benefit they need not assume any downside risk either. The seller could structure it so they split profits and losses proportionally, but that's a completely different business arrangement, more resembling a partnership than a contract.