It's not just the direct hourly operating cost, it's that they were able to buy the less fuel-efficient planes for dirt cheap to begin with. When you can do t

It's not just the direct hourly operating cost, it's that they were able to buy the less fuel-efficient planes for dirt cheap to begin with. When you can do that, and your fuel usage isn't a major portion of the operating bill to begin with, you care less that it burns slightly more fuel each short trip per day.