Nathan, I recommend you stop trying to take the concept of 'authenticity' as a real thing seriously.
It's less the lack of authenticity that bothers me and more the fact that these novels end up serving a distinctly ideological function, one with which I disagree and to which I object.
I see no contradiction here. Romantic fantasy novels are all about authenticity, they are not known for their empiricism. Why single out the Amish? Nobel Savage fantasies are all over the place.
I imagine Nobel Savage fantasies are dynamite!