Jimmy,
It's fairly simple, in my opinion. Satan happened.
Clearly, the commonality is that the evil one, through whatever means, infiltrated the minds of these young ones, and convinced them that their salvation was at stake.
I would like to tell you that trying to figure it out is akin to knocking your head against the wall. It is painful, and it doesn't get you anywhere.
Forum:
"Cults," Sects, and "New Religious Movements"