Odd.  Grew up in PA and we had to obtain licenses for our bikes if we wanted to bring them to school.  To get that, we went through safety inspections and riding classes, and they taught us to behave like cars...inclusive of traffic direction.

What's really bad about riding the opposite direction of traffic is the bike is in an area where the motorist isn't looking.  About 6 months ago I almost pulled out on a lady riding the wrong direction.  I was making a right turn on red into a divided road, and my focus was primarily traffic coming from my left.  There were no pedestrians in that intersection.  Just as I was beginning to pull out, I looked right to the lane I would enter, and there she was.  Fortunately it was nothing more than a scare.  But, in that situation, what reason would I have looking to my right?