Humans are not unique when it comes to breaking classification rules: dolphins are mammals, although they have no hair after birth, and the platypus is a mammal despite the fact that it lays eggs that develop outside of its body. Humans, moreover, circumvent "nature’s plan" in myriad ways: refrigeration, immunizations, and automobiles all interfere with "nature."
Everything in the world – air, trees, breast milk – bears the marks of human activity, and "nature" does not exist anywhere in pristine form. If it did, it would not be necessarily superior. To argue that breastfeeding is optimal because it is "natural" implies that what is "natural," by definition, is healthier and morally preferable, an assertion that scientific evidence does not support. "Natural" is not synonymous with "better." Preferring to breastfeed because it feels more "natural" is an aesthetic choice, not a matter of health or metaphysics.
No compelling evidence indicates that skin-to-skin contact is a "vital component to human development" or that only breast-fed babies are held "safely" during feeding by their caretakers. Such assertions are fraught with moral assumptions about women who choose to bottle-feed. The implication that parents who formula-feed cannot bond as well as breastfeeding mothers with their babies is groundless. It is contradicted by strong evidence that bottle-fed and adopted babies, as well as children who experience extreme deprivation in their first years, form emotionally healthy bonds with the people closest to them.