Ok, one more time, since no one has given a clear answer to my question, but has instead tapdanced around it?

You could argue that has no other purpose. It's only for making babies and it should only be done by people who are prepared to raise the baby in the best environment, which is with a mother and father. That is the ideal situation. If we lived in a perfect world, this is how it would be. But, we don't live in a perfect world.