We are shaped by hundreds of millions of years of evolution. Parts of our brain are hard wired because those who didn't share that hard wiring didn't survive as well as those who did. We are mammals and mammals have been around from the beginning of the dinosaurs, 230 million years ago. All mammals care for their young. For that matter so did some dinosaur species. So do modern birds. It is part of our DNA to try to give our personal DNA that is in our children a head start over everybody else's DNA. That is just the way nature is.

People will always want to give their own personal children a better edge than everybody else's children. If you try to block them from doing that, they will revolt. They will accept giving everybody's child a good chance, but they will still want to help their own kids.

The above is a general statement. There will always be some individuals that depart from it, but the masses won't.