This generally means the aircraft is the best choice to prop up customers whose business is slowly failing, and would be severely harmed by having to invest in improvements to the supporting infrastructure. This is not altogether surprising since air travel has been increasingly commoditized, so aircraft operators who don't price in long term capital improvements can outcompete (or for the worse ones, just stay afloat at all) for some period of time.

So it's no different than any other business with eye-wateringly expensive infrastructure, really.