Yeah, okay. So much less cruel to just trap and kill them all. Unless you've got a secret cat utopia where they can all go to.
Actually yeah that might be needed in some ecosystems. Having cats indoors doesn't guarantee they won't escape unfortunately. It should probably be illegal to buy and breed cats in many places around the world. Laws requiring they all be neutered would also help. I know Spain spays and kills feral cats regularly.
We need to find better, more sustainable, more local animals to replace them with.
Africa where they come from