I think that mother nature figured out how to have healthy garter snakes long before we came meddling around. We need to look at a bigger picture here. Bottom line is, no single food is "the best" or "complete". Garter snakes eat a wide variety of foods. (There are exceptions as some garters will only eat worms and slugs) It's up to us as keepers to figure out a wide variety of foods that our snakes will eat. My concinnus love night crawlers and they do get them but it's only a small part of their diet. It would be far too expensive (and just not right) for me to feed them exclusively on night crawlers since they also love mice and fish.

If your snakes take something besides night crawlers or any worm, for cryin' out loud, give it to them. It can save you money and cleanup time, AND make your garter healthier.