I'm quite disturbed by some videos I saw on youtube of people who feed
live mice to giant centipedes, frogs, and some other primitive
predators.

Mice are mammals like us, they are quite smart animals. Those people
say "it's just nature" but it isn't. Nature doesn't dangle a mouse by
the tail to such primitive predators in a glass tank, or poke it with a
large feather repeatedly and for minutes into the way of harm despite
its otherwise successful attempts to escape until it's caught. Nature
also doesn't make an entertainment out of it, laugh audibly at the
spectacle, and put it on youtube. Mice are also not natural diet for
these primitive predators (grasshoppers, crickets are).

http://www.youtube.com/watch?v=8avbYNeg738
http://www.youtube.com/watch?v=ZKXG_kcGhug
http://www.youtube.com/watch?v=8CL2hetqpfg
http://www.youtube.com/watch?v=3APJA0EedSE