I suppose I will back up what I said, because I'm obviously wrong, and I feel like I implied something I wasn't meaning to. I have found that most of these communities have a much larger community focused on genres, and even within those that love literary fiction, and who write literary fiction, the emphasis has been on selling and marketing towards commercial fiction (which overlaps significantly, but the commercial aspect as something more prominently focused on).
While I'm still quite a newbie here, I've read a LOT of threads, and the vibe is MUCH different than those in literary fiction communities I have been a part of elsewhere. I don't mean to imply anything other than there seems to be a different focus, which would explain the seeming hostility that the OP has noticed.
To clarify even more. I feel like my statement as being perceived as me saying that there isn't overlap between these different communities (there is), but I mean instead that there is a different feeling. You're right that there are a few MFAs in various genres (they're relatively few and far between, comparatively, but exist, and are marvelous), and I don't doubt that there are plenty of people who are doing great work here with many interested degrees in backgrounds. But the focus on this site, and many others, is in placing work commercially, and finding the correct genre in which to classify it. There has been a LOT of scoffing at the idea of literary fiction, and fiction that seems to not fit into a particular genre category is often encouraged to be pushed in that direction. This isn't because of educational lacks, or anything bad, but a different focus.
Btw, I am one of those people within a PhD writing program. The vibe, advice, feedback, and atmosphere here is extremely, extremely different from other writing communities I have been a part of. This is part of the reason why I'm here in the first place.
The PhD is still pretty new, and it has a very limited use. The MFA is still considered a "terminal degree" in that it's all you really need to get a job teaching writing at 99.999% of places. The most important thing is your publication record for that. The PhD just makes getting a job easier. The PhD is a literature degree with a creative dissertation (hooray, not having to write 200 pages on Milton or Pynchon or whatever). While there are some really incredible writing programs throughout the country, MOST schools are smaller, or have much smaller writing programs and don't necessarily have the luxury of hiring someone to teach only creative writing (or, if they do, they can have only one or two on staff). The PhD gives you the credentials and experience to teach literature courses as well as writing courses, so hiring committees have more flexibility in bringing writers in. So even though it's a creative writing PhD, the focus is less on the writing aspect, and more a hybrid academic development.