“How can an airline make a profit from an unprofitable refinery when the oil company’s business is refining?”
By in-housing the ‘Crack-Spread’, and middleman profits.
It also takes a critical supply chain out of someone else’s hands, and puts it in yours, at what you know will be your most profitable hubs, after the slot-swaps.
It’s not a new idea. Airlines have been in the oil business before, and Delta has been all along. They owned and ran a pipeline with a subsidiary, Epsilon Trading, which is still in the av fuel business.
United has also been in the oil biz.