I'm curious, don't you have the same problem with rental planes as with rental cars that while the cost of the pure travel time might not be so bad, what really gets you is that after you get somewhere, it just sits there, still costing money until you get back days later?
I know that engine on time is particularly expensive for airplanes whereas for rental cars it's no factor, but I would also expect the pure rental time to be expensive for airplanes if you use it to go on trips as opposed to standalone flights ending back at the home airfield?
Many rental planes are rented for engine on time only. You can’t push it too far (take the plane for a year for two hours of flight time) but you can do weeks. I’ve done it.
I know that engine on time is particularly expensive for airplanes whereas for rental cars it's no factor, but I would also expect the pure rental time to be expensive for airplanes if you use it to go on trips as opposed to standalone flights ending back at the home airfield?