The way we feed live to our snakes is nothing close to natural as in nature, the snake and mouse/rat do not find themselves confined in an area that is a couple square feet, unable to escape.
It's like saying that, because it's natural, I should release live rabbits and fawns in my living room for my dog to kill and eat for her dinner. I'm also not going to release song birds, rabbit pups and rodents for my cats to hunt and eat because that, too, would be 'natural'.
There are understandable reasons for feeding live. 'Natural' is not one of them.
Those are domesticated animals. You can't compare a snake to a dog or a cat. Obviously if people are having an astronomically better feeding rate with live, they prefer live! Have you ever had a dog that just won't eat because he's crazing a live fawn?