Well, killing at least.
You see, we have mice. And not the pet kind. And while we bought the humane traps, I'm left with a dilemma. The mouse can be released to the wild, thereby learning that he can get a meal left out for him at our place. Or he can be killed, which will if nothing else mean one less vermin in our house.
Better yet, the collective effect of killing mice is hoped to have a deterrent effect -- with luck, the mouse community will see our house as a kind of black hole, or maybe Guantanamo.
(Yes, I'm endorsing an argument about mice that I don't endorse about humans. Your point?)
So to me, the choice would be clear even if I didn't detest mice. Which I do. If you sell me a humane trap, you're selling me a bug, not a feature. I want these bastards dead.
Me: The Dick Cheney to the Global War on Mice.