behind "Assuming that people adhere to the rules of the community out of choice (there's no reason not to assume this), I respect any group that practices their faith as long as causing no harm to others. I can actually see how living a simpler life may feel more appealing to mainstream western culture, each to their own. "
It's not really like that though. So looking at the brethren (who I know more about) you are born into it. No-one is allowed to join, and they lead separate strict lives. They are taught from a young age that outsiders are ungodly, immoral and so forth. It is not allowed to access any form of media - radio, TV, newspapers, internet. It is a closed community, and they mix with each other. People who do not follow the line can be forced out, and they often commit suicide. It doesn't happen very often as once you have been told to leave, or decide to leave, you will never be able to see or speak to any of your family or friends again, and you are unlikely to know anyone else. They all work together, what do you do for work. That sort of thing.
It's not like, say my uncle who joined what my dad describes as a cult
in the 60s, did it for a few years and then left. It's not to do with choice at all.
Like I say I know more about the brethren than the hassidic jewish population but from what I have read there are parallels. No access to media, very closed, "traditional" roles for men and women, large families, antiquated dress codes, women having lots of rules around hair and so forth.