Back in 1958 (I was 7 at the time) I remember my father in a heated discussion at a church function. It was memorable because it was the first time I think I ever heard my father so contemptuous and for the phrase "Those BBs, they Drink Wet and Vote Dry".
I knew what BBs were, after all I had just gotten a BB gun for Christmas that year. What I couldn't figure out was how they, the BBs, could drink. It wasn't till years later, after we hand moved to California, that I found out that the BBs my Dad was talking about were the Bootleggers & Baptist. The issue was if Oklahoma would stay Dry or go Wet (that is would prohibition be ended). Everyone new were the Bootleggers stood but they didn't have the votes to keep Oklahoma dry. The key was all of the voters who would drink themselves under the table on Saturday night and then go to church on Sunday and denounce the evil 'wets'.
So what's my point? That hypocritical behavior by social conservatives is nothing new. It has a very long tradition in American politics so don't be surprised with Sen. Vitter. The good Senator is just following the grand southern tradition of "Do as I say, not as I do."