Show me some evidence of your allegation that humans have “always” exploited one another and even children. While I’ll give you that there have always been mean, manipulative, exploitative people in any society, most humans, once they recognize that bad person, shun him or her and effectively put an end (or a big limit) to their damage. And in nearly every society (with some exceptions, of course), children were considered sacrosanct, the future of the tribe/people and to be cared for and protected to best of the whole tribe’s ability.