Because normal crop dusting airplanes: are big and heavy, forcing big batteries. Hotswapping 10kg battery pack is much more feasible than hotswapping 100kg one.

Because normal crop dusting airplanes: are big and heavy, forcing big batteries. Hotswapping 10kg battery pack is much more feasible than hotswapping 100kg one. You can work whole day using 3 batteries regardless of size, but having to swap 10kg battery every 5 minute is more feasible than swapping 100kg battery every 30 minutes. Those planes cant land right at fields edge, so big chunk of energy in its battery would be needed to fly to and from nearest airstrip.