I don't think it's fair to the cats. It's not their fault. We created the problem years ago with people letting their cats run loose and multiply! We need to educate more people and have stronger laws to fine people if they continue to not sterilize their pets. That's where the problems starts, abandonment and not getting he cats spayed or neutered. 
Now it went way out of control with their population rates and of course the poor animals have to suffer the consequences. Instead it needs to be the people who need to be responsible and get their pets fixed!