We've heard about tremendous amount of money losses even leading to famine due to crop destruction from locust infestation over and over again, but all these grasshoppers are a valuable protein, probably way more valuable than the destroyed crops. Although most people from many cultures won't eat such insects, these can be ground to flour and stored to be fed to omnivore livestock like pigs or sold for profit or exchanged for grains.
Is there edible energy in the insect swarms? Can this be made into livestock feed? If not, is the reason this isn't common practice biological or economical?