Super-size grasshoppers would make an awful plague
Because of grasshoppers, full lands have gone to waste, and societies have starved or been forced to migrate. The Greeks mentioned this plague; the Catholics and the Muslims were too scared because of how quickly they reproduced and ruined plantations.
If a plague of regular-sized grasshoppers was enough to devastate whole towns, imagine what would happen if this gigantic sample was to reproduce. An invasion of these monsters sounds like the plot of a terrible apocalyptic movie.