I think the show overreacted. Personally, I would have smacked myself for asking someone from deep Louisiana a question like that and expect something good. However, I think the same view I have on christian gay marriage applies: It's their club, they decide who's allowed in. I don't agree with the show's decision, but it's their right to fire an actor for whatever reason they please.
Anyway, I'm pretty sure that they would have responded differently to the case if they'd known what kind of shitstorm this would evoke.