It's not that neutering animals is particularly cruel, considering all the available options. We just stop caring once it's a carcass. Neutering is expensive, intensive, and if the destruction of local wildlife is the problem, neutered animals still eat. An outside gib adopted us growing up(Mom named him Amber before we sorted out his anatomy, he didn't seem to mind). He would bring us songbird gifts. So, it doesn't address the problem. If you've already captured the animal, getting rid of it was the goal. So really, why bother capturing it? Shooting things in live traps sucks. But I guess trapping can be a tool to be used, and leg traps hit unintended targets enough that live traps + culling might still be a legitimate thing in some areas.