Flying has got to be more efficient than traveling through a forest. As a person who spends a lot of time in the forest, there's a ton of impassable obstacles.

Flying has got to be more efficient than traveling through a forest. As a person who spends a lot of time in the forest, there's a ton of impassable obstacles. Cliff faces, streams, briar patches, downed logs, etc. The robot on the ground would spend more energy in the forest than the robot in the sky. I think being in the sky also helps keep them from being a target for looting.