The two markets are not so similar. Air travel can only support a limited number of suppliers (in some locations this number is zero), since commercial airplane

The two markets are not so similar. Air travel can only support a limited number of suppliers (in some locations this number is zero), since commercial airplanes are very expensive and require the use of valuable airport facilities. Housing isn't like that. Lots of investors can afford the note on a small apartment building. If one developer pads her profits, another one will undercut her.