Since you go through so many, have thought about raising your own? Quite a few people who raise chickens have meal worms and a lot of reptile owners do also.When you put it that way, I've got no good defense. I'm sure it is cheaper by the pound to feed virtually any cut of beef.
This Robin we feed won't eat dead worms or bugs. She's spoiled!
We use Petco.com and get 5000 large for $37.

