Drones vs trucks

Air Traffic Controller For Drones

Drone deliveries could considerably reduce the energy (and therefore cost) required to deliver small packages from delivery distribution centers to the consumer’s home. These last few miles of the delivery process are most often done by ground based internal combustion engine (ICE) vehicles. Drones would reduce energy expenditure by virtue of the fact that most of the energy consumed in ground based delivery is for purposes of propelling the heavy ICE vehicle itself.

Are drones really more energy efficient for package delivery than trucks, given that (1) trucks amortize energy cost across many packages and (2) trucks don’t spend energy to stay up in the air?