L. E. Modesitt (he's a science fiction author) wrote a blog post not too long ago, that I'd wanted to comment on, but never got around to doing so until now. While the post is on genre fiction and its relationship with the "literary establishment", he makes a good point further on in the post - which is what I was inspired by.
The problem isn't that of a "literary" establishment, but the fact that any culture is composed almost universally of individuals whose thought processes and preconceptions are tethered to the present reality in which they live. That present reality is the basis of their preconceptions. Some can speculate slightly beyond the here and now. An even smaller number is comfortable in reading farther beyond the "now." But... the farther one goes from the comfortable here and now, the fewer individuals there are who will make that leap, and even fewer who are comfortable with it. Even in the theoretically more open society of the United States, there are tens of millions of people who cannot conceive of, let alone accept, any sort of domestic arrangement besides a two-partner paternalistic, heterosexual union sanctioned by a religious body. There are possibly more than a hundred million who have no understanding of any theological system except those derived from European Christianity. Effectively, the vast majority of individuals from such backgrounds are self-alienated from science fiction and to a lesser degree from fantasy.
It seems a strange quote, perhaps, but the context is relevant. I am a writer and to me, these things pop up all the time. I have to deal with individuals who perceive things only through the small looking-glass that is their life. Even with my own insecurities regarding poly, I'm still open-minded enough to view the world around me as a place with all sorts of possibilities. When I came out to my father about our marital arrangement, the risk was relatively minimal. Nyla and I have made a decision not to tell my mother (the biological one) because she is of the above-mentioned group of people. Though the irony of her having had two affairs in her life - ending both marriages she's been in - is not to be lost.
A lot of people, when I tell them about my situation, ask - almost instantly - so why did you get married? As though by getting married I nixed all other possible options of relationships in one fell swoop. What they can't grasp is the idea that we made this decision after we'd been married for nearly two years. It came upon us by accident, and we recognized the natural way of things for ourselves. We didn't choose it; it chose us. We like it that way.