[elamje]

Additionally, people forget the extra energy cost of fighting gravity. It takes a lot more energy to use a motor and prop to directly resist gravity, rather than using a static object like a wheel. Energy loss fighting gravity with a propeller >> energy loss fighting wheel friction.

[garkin]

Energy is not the only thing you should care about freight and human logistics. Logistical resources of cities are scarce and it already badly affects labor market there.