What a strange view of America's past you two have.
It's like they say, truth is stranger than fiction.
PS- Though personally I don't see anything strange about it. Human culture and society does not and never has existed in a vacuum. Really, the main function of any given society/culture is to serve as a buffer against environmental pressures (natural or man-made) so that the group can survive. While, like most things that are man-made, there will be parts that serve no function, the function of practices and beliefs which seem strange are often misunderstood or not seen at all without looking deeply.
For example I remember there was one culture where cannibalism was used as a way to strengthen ties between families. As I recall a man would eat some of his in-laws after they died as a favor to his wife's family. It was believed this was part of a process that would free the trapped souls of the in-laws. He also did some ritual hunting of birds, the soul having been next caught inside the bird, finally freed after it was killed, as part of this. Needless to say freeing a loved ones soul gains you a lot of gratitude, and families that stick together live longer in harsh environments. Of course this ritual may have had its origin in a time of famine, we don't know. But it helped pull the people together even if it was (unbeknownst to them at the time) demonstrably bad for them*, just as being too insular and conservative is bad for a group though they may not sense that it is.
*Cannibalism can lead to serious illnesses, it's how we got mad cow disease.