If it’s within an organization’s means to spend $100k (within means being the key part) to be able to destroy 500 dollar drones in a way that increases the ability to win compared to not having it, then purely from the war perspective, it makes sense.
Of course, the entire concept of war is laden with waste and destruction, so it’s almost never in alignment with the economically and environmentally optimized choice.
The largest militaries have access to such an insane amount of money that almost anything that wins better will be purchased, despite the monetary return not justifying the monetary cost.
In life and death situations, a soldier backed by that money isn’t going to care how much money they wasted. Just that they remain alive and the enemy loses.