This is a great idea if you look at the math, but almost impossible to get over the emotional response. Maybe processing the grubs/flies into something less recognizable would help, but at some point you read the ingredients and you're back at square one.
Disgust seems to be one of the more irrational and risk averse emotions, which makes sense - guessing something is disgusting when it's not has little risk, but guessing something is not disgusting when it really is dangerous carries great risk.
Interesting problem especially when recoginzing what damage our current meat production is causing, plus the base inefficiencies of it.