Right, but what if it took one quick swipe? Like beheading someone? Does this make a difference? If you shoot a nuclear bomb big enough to destroy the world's population, you're not going to hear that person screaming, your going to hear a big explosion and that's it. Plus, by shooting a nuclear bomb, you may feel bad as you have pressed the button, but regardless, it's too late. In the same way, the beheading someone is like pressing a button and then it is too late. Stabbing someone: takes multiple times and thus you have multiple chances to stop.
Another perspective, let's pretend God is not as loving as we think he is. Are we considered his property? If I own a chair and break it, I can do so cause I own it. Then again, if I own a hamster, I cannot legally kill it. In the same way maybe God wants to destroy the non-living property and save the living?
Again, just an idea.