There are two separate issues here -- yes, ABC isn't shying away from the issue because they want the buzz. But Leah's personal issues with having left Scientology are very real, and she doesn't have the same motivations for doing the show that ABC does for casting her.
She's scared for sure, and with good reason, given the group's history. There is such a thing as "hiding in plain sight" -- when some want protection, they doin't go into hiding but rather stay in full view of others, so that people would notice if something happens to them. I feel for her -- ABC may be exploiting her situation for their own benefit, but that doesn't make her plight any less real. That's why I'm glad they're not ignoring it on the show.