I just want to say that volume does not say anything about profits.
All depends of the profitmargin. If during the year the profit is average $3 a barrel, and they could buy now at $0, at a selling price of $30 they make now $30 profit a barrel instead of the usual $3. So profits are 10 times higher. Or in other words: in normal times they needs to sell 10 times more to make the same profit as they made on this $0 deal.
Example:
If I trade 10 ES, notional value around $1.5million at 3,000, 1 point move can make me $500.
My neighbor who is producing icecream sells also for $1.5million (iccream, no ES futures) with a 30% profit margin. He probably makes much more profit than me as he should only have a net profitmargin of 0.04% to beat my profit on the same transaction amount.
There are each year companies that sell for billions and still end up with a loss. Why? Because they have a bad or no profitmargin at all.