For me the exciting part about bug farming isn't really their use as food (for humans or animals) but more their potential to eat "real" waste (like things that birds and mammals shouldn't eat) and then be turned into non-food items - like chondroitin or have other derivatives made out of their chitin.
Right now it's not very efficient but with some selective breeding (or faster, GMO mealworm gut bacteria) they could start working on the landfill issue. Their poop would have to be incinerated since it would concentrate flame retardants and other toxins, but we might be able to get something useful out of them.
edit: i have a box of mealworms that I wanted to try feeding just styrofoam to to see how many generations it would take to have mealworms that thrive (not just survive and turn to cannibalism) on the stuff, but i felt bad, now they eat kitchen waste and shredded paper.