Censorship

I don't know if this is a nationwide group or just something local but in my area there is a group called Reality Check who are making the rounds to town boards, asking them to pass a resolution calling for movies that include characters smoking cigarettes to be R rated.
In my view, ratings are just another form of censorship. True, movies, books and magazines that are rated in one way or another are not REALLY banned. Never-the-less, it is a form of backdoor censorship.
Maybe you are opposed to smoking, sex and violence. Fine. Good for you. Don't smoke, have sex or commit acts of violence. But to exclude depictions of these realities from fiction is, to me, a violation of free speech.
I think it is up to parents to monitor what their children read or view.
Oh, parents need help? Yes they do. Some one needs to tell them to be parents and stop asking the government to be the parent.
What do you think?