I got lost in my own snark yesterday before I could make the point I meant to make, and now it looks like the point will have to wait another day, since there's a couple of things to deal with in yesterday's comments.
To answer Anon's question, oh yeah, explcit discrimination on the basis of Teh Gay is totally, totally legal. As PJMB friend (and authority on matters theological) NS points out, if the institution is private, they can discriminate on some pretty sketchy grounds. Remember, Bob Jones University* barred interracial dating among its students until 2000. I.e., black kids could get kicked out of school for holding hands with a white girl. When when they dropped the ban on interracial dating, they did so for purely political reasons, not legal ones. So, yeah, discrimination against GLBTQ people? Totally legal.
As for NS's larger point, this sort of discrimination is actually uncharacteristic of (I'd say) the majority of religious schools looking for philosophers. You read through the fine print of the different ads in the JFP and you get a sense for how to read between the lines.
For example, when you see something about "a learning community founded on the principles of Jesuit (or Franciscan, or Benedictine, or whatever) scholarship", that's a good thing. It's an especially good sign when they say explicitly that they're welcoming to people of all faiths, although where that leaves us atheists is an open question.
But when you're reading through a job ad and you see something like, "Wheaton College is an evangelical protestant Christian liberal arts college whose faculty members affirm a Statement of Faith and the moral and lifestyle expectations of our Community Covenant"--when you read all that, that's bad. Really bad. Because you can bet their "moral and lifestyle expectations" are going to have a lot to do with old white guys telling everyone else who they have sex with. Or even who they can date.