The placenta is essentially a body part of the infant that consists of a mass of blood, blood vessels, and connective tissues. It cannot possibly contain any nutritional value that is unavailable from food sources. And eating it is disgusting.
Placenta – Worth Trying? Human Maternal Placentophagy: Possible Benefit and Potential Risks
You are ignorant.
Most animals eat it because it DOES contain enough nutrients and energy to power the mother while they are not able to hunt. It also protects the two of them from predators.
Stop being so preachy. Nature is a wonderful machine. It has thought of everything. Just because you have no predator and plenty of food handy, it doesn’t change to normal equipment you are born with.