As to this point, I don't see any of your arguments being anything but simple contradiction.
I'm not saying, "hay every1 go out n feed ur garters bugz!!11"
But obviously if it triggers the feeding response and they like the food, why not give them it?
Just think of all the variety we can offer our garters: worms, fish, amphibians, leeches, beef heart, pinkies, and now wax worms. Wax worms are very high in fat but are considerably more digestible than pinkies, which may cause liver problems. So I see no reason why not to use it as a treat.
Also, I'd like to note that none of the males seem interested; And the females, excluding Don's, have all given birth and are currently be fed back up to a healthy weight. Insect larvae ARE very high in protein...