@TwinkleSnort, yes, sterilizing an animal I obviously to keep it from reproducing. I'm not so sure about it being healthier for an animal based on the fact it isn't healthier for other animals, namely humans. When men are accidentally castrated and women have hysterectomies, they're given HRT to supplement the loss. Sex drive excluded, the lack of estrogen in women and testosterone in men causes other medical maladies, I have a hard time believing removing healthy organs from any other animals aside from humans only nets positive results with no negative.
My dog that didn't have his balls chopped off never actually jumped anyone. It sounds like the primary motivation for doing as much is to prevent that kind of embarasing scenario (considering it's no longer the 70s and people don't allow their dogs to roam the neighborhood freely to get knocked up) which is on part with being annoyed by scratched furniture. I'd say it's less worse because at least getting your legged humped doesn't lead to any property damage.