[Harmless Teddy Bear]

An alien from another planet would look at this and conclude that all Earthlings are insane, and also stupid, because they cannot see the deep contradiction between these two situations.

That is because it is hard to find people who will take discarded pets as they have little to no value.

Finding people to take Human Babies is easy and they will even pay for the privilege. Because Human Babies have intrinsic worth.

I would say a species advanced enough to fly in space would probably understand this easily.

[robowombat]

There are private shelters who will take dogs no questions asked. A friend works for such a place. People leave dogs secured by leashes on their front porch regularly.