Interesting. A very complex and organized subculture. I did not know that polygamous households were still around in such numbers.
There has to be a great deal of paranoia and alienation directed towards the non-Mormon culture out there, be it Hollywood, Dixie, Midwestern or Yankee - whatever the ‘gentile’ cultural base. It does not sound like a comfortable place to be. Besieged from the outside, driven from the inside, and so many in house details to keep quiet.
And if the older men in those communities need young women as wives, imagine what happens when the young men reach an age that they present a threat to the men as possible romantic interests? They are outcast, with no belongings and no real education. They're called 'lost boys." There's been a documentary made about them. There are charities to deal with them. Here's one.