Why?

[Stefan-A]

This is most likely the reason why we humans rule the Animal kingdom. If it wasn't normal, our ancestors didn't take any chances and would probably kill anything out of the ordinary. Just a human life saving technique that's gone out of style in our civilization, now that we can relax and understand how the world goes round.

I don't see how it could have gone out of style. It's still necessary and beneficial for us to remove threats from our environment. Now that we've killed off the snakes (and large carnivores) in our environment (the developed world is heavily urbanized, which sort of rules out the "flee" option), it is safer for us and we can relax and pretend to understand how the world goes round.