You won't find your idealized conservative family in the movie, but I'll bet if you go see the movie, you'll come back to this thread and report that I'm right: You've known these characters your whole life. You'll be able to point right to people they remind you of.
That's what I was thinking when I saw the trailers. I remember seeing the Big Chill (one of my all time favorites) and having someone tell me, "But I don't know anyone like them."
Yeah, like the mom who wishes for all of her boys to be gay. I mean, what mom doesn't wish that? Then there's the multi-racial, handicapped, gay adoptive parents...there are four couples like that right on my street!