> and expresses that view
In my opinion, it hinges upon the expression. If they are pleasant at work then one day you find their Facebook profile has a racial and homophobic slur, I don't think that's interfering with the work environment. If they say the same thing to you at work, then you can talk to HR.
Unfortunately, by drawing the line here I'm allowing the possibility that you have to work with someone you don't like. Sorry about that. I think that's part of a larger problem, and I'm open to hear solutions for not-liking-someone-but-being-part-of-a-society. When a person is engaging in poor behaviour in the work context, you can use the mechanisms in place to correct that behaviour, but keep in mind that the goal is behaviour correction not crucifixion.