I have usually found them to be of the elder/pioneer class. Some MS's came into that class too, especially those who are working there way up.
The congregation that I am associated with several years ago did have a notorious family that even was "Holier" than God. Sadly, they moved into a congregation to where one of my mates lives in. They had caused a mass exodus of those in the congregation to leave and move into neighbouring congregations, but they still work in the the town they moved from. They would rather travel about two hours a day then associate themselves with that family in the congregation. Even though the father if that family is no longer an elder (he was actually forced into stepping down, but his wife went around telling that 'he had volutarily stepped down for the benefit of the congregation") that congregation is still in turmoil, even though they had two elders sent by the society to take care of the situation. As long as they are in the congregation, they will never recover from the hurt that they inflicted and nobody will move in there. They have even scared newly associated ones by their actions.
The stories that he tells me are quite funny and disturbing, and you really do have to shake your head with what they are doing to that congregation. They had moved into that congregation about 2001, and it looks like that they will most probably stay there until somebody does give them a death threat again. That's the reason why they HAD to move out of the congregation that I'm in now.