Why debate this? Well some of us feel very bad for the suffering we have to inflict upon these innocent animals. If the snake kills it, well that is as nature has deemed most fit and is not really for us to judge. The snake kills how it kills and has no choice in the matter. But if I kill it, I do have choices, and I want it to suffer as little as possible. And I think most people want the same. 2 minutes of suffering the intentions of death is a lot of suffering compared to 2 seconds. I think anyone who's been near death would testify to that.

I'm pretty sure the effectiveness and effeciency of mouse traps is debatable. Or, it's not guaranteed to snap the neck and kill, even if everything goes right. It sounds good, though. I'm just not sure on their track record, and I think it leans toward less effective than is ideal. Plus, some people just don't want to deal with something so grapic. Gas is easiest on the one doing the killing, but I think directly destroying the brain is the quickest and puts the animal through the least amount of suffering of all out options.

I think that's all there is to say about that. If you just don't care much, then gas is not too bad an option. If you want the most humane (i.e. quick and painless), I don't think that is it.