Hrm... I thought some snakes can't be trained to eat non-living prey? The school snake I took home on long holidays when I was in High School would only eat live prey... I couldn't bring myself to do it, and wound up keeping the mice I was supposed to be feeding him as pets. My mom's neighbor rescues snakes though, and raises and kills his own mice and rats (so he can be sure they're raised and killed humanely - his will eat them dead, but only if they were literally just killed). He tried to feed mine one of his dead ones, but he wouldn't take it so he gave him a stunned one instead, and did that from that point forward.
He NEVER makes sport of it though, and even has several rats and mice that are his pets, as even he can't bring himself to kill them sometimes. Some people are just sick though, and shouldn't own any animal, let alone a wild animal (that shouldn't be kept as a pet anyway - but that's another argument entirely) like a snake.