I hear that its pretty difficult to convert to Judaism .... and I
imagine its even harder to become Old-Order Amish. As I understand it
Dark-skinned people can never ascend to the highest order of heaven in the
Mormon church. So if your question was "Are there belief systems that exist
without trying to sell conversion" the answer is yes....but I suspect the
morphology of these systems vis a vis child rearing, shunning, etc.
probably have similarities.