Hulu just added this season and I watched the episode. Leah is definitely a special case because her mother wanted to get out and Leah moved up when she got acting roles in stuff like King of Queens. It was interesting how the one sister remained just enough of a Scientologist so she could still communicate with her family. But All of Leah's family seemed to make a break at the same time.
Mike is probably more typical. He may have been a spokesman for Scientology, but he was abused more because he was in the Sea Org. When he left, his wife stayed, the kids stayed and his mother stayed. That emotional blackmail of disconnection seems to keep Scientology members in the fold more than anything.