You run into the natural monopoly of airspace instead. There's more room up there, but owners of the land beneath and users of other aircraft alike have a vest

You run into the natural monopoly of airspace instead. There's more room up there, but owners of the land beneath and users of other aircraft alike have a vested interest in the skies not being a free-for-all, and sure enough it's government agencies stepping into the air traffic control and regulation breach.