Interesting premise ... and I remember thinking at the time that it was a little far-fetched.
In my dreams ... or, rather, nightmares.
Right now, most people can distinguish between tobacco, which has zero nutritive value, and cheeseburgers, which have some properties as food. If the lefties convince enough people that they're right about this and other parts of their agenda, then we'll have a lot more to worry about than where to find a burger den. Every day, we live in the middle, between the extremes on all of hundreds of issues, and a slight movement towards one side or the other is not going to bring people's lives crashing down.
Face it, more people can find something wrong with crack cocaine than with aspirin, and more people can find something wrong with tobacco than with cheeseburgers. That's how the balance is set. If you'd REALLY like to stop the slide, then persuade people that the extremists are misguided, but Chicken Little "the sky is falling" rhetoric is not going to convince anyone.