There is demand for first class seating from nearly 100% of fliers. They're just not willing to pay what AA is charging. This isn't a supply and demand decision. Econ 101 says that means AA should reduce the price, but capitalism in practice says the constant desire for more profit and the monopoly that most industries have been allowed to grow and maintain means never lower the price and find a new way to fuck the plebs who don't even own a single yacht.