Its never about compassion, its about how cute it is. Bugs are gross, so therefore their mass destruction doesn't even register as a problem.

yet to make a patty you need oodles upon oodles of bugs whereas one cow can be made into multiple burgers

It doesn't take anywhere near the same amount of resources to produce enough protein from grasshoppers as it does from a cow. The feed-protein yield is far more efficient for one thing [1:10 in cattle vs 9:10 in grasshoppers] and the resources you can use as feed are also far less restrictive. There are companies which hire out goats for example to clear patches of vegetation because the goats can and will be able to eat and digest certain vegetation that other animals cannot. The same holds true for a lot of insects hence why things like locust swarms are so effective at strip mining plants. You can feed grasshoppers cactus plants if you want, you can't do that with cows.