Political Correctness and Movie Ratings

Recently the MPAA, under a lot of pressure from the anti tobacco lobbying groups, agreed to begin using the presence of smoking in a movie as one of the criteria in its rating system. Previously whether characters in a movie smoked was not considered when rating a movie. Read the story Here. While they haven't yet committed to it,they are under heavy pressure to give an automatic R rating to any movie that depicts smoking under any conditions besides those showing the smoker dying or in the hospital of smoking related health issues.
I'm no fan of smoking. I think it is a nasty and expensive habit. Cigarettes cost a great deal. And yes, I do know that a lot of that cost is artificially inflated by law to try to force people to quit. But that doesn't change the fact that under our current system,they are very expensive. The other thing is that they make you smell pretty bad. Unless you are used to the smell, it is actually nauseating. So if you are already hooked on smoking, you really should do your best to quit just for those two reasons. But of course it gets worse. Smoking is also extremely bad for you,and will likely kill you. So you really should stay clear of it.
I said all of that to make it clear that I don't like smoking. The problem is that I don't think that our society should attempt to enforce codes of behaviour on people simply because we don't like the behaviour. Codes of behaviour should only be enforced when the objectionable behaviour harms other individuals besides the one doing the action. Since I don't think smoking harms anyone but the smoker, I don't see any reason why we should try to force people to stop. Yes, I know all about second hand smoke. Do the research. I think you will find that all of the more modern studies show that unless you are living with the smoker, second hand smoke is less dangerous than the smog you get in a big city.
So I ask, does smoking by characters in a movie hurt anyone? Would it have been a good thing for the Lord of the Rings movies to be rated R?