All the feeder insects are not recommended as a food sourse for the garter snakes ??

[Stefan-A]

So by that logic feeding whole mice isn't good due to the keratin on the nails?Would it be better to cut the feet off?

The fur is the first thing that comes to mind. The short answer is that even they can't digest it, it doesn't mean it's a problem. Those animals that can't pass it, regurgitate it.