There is a difference between using something (and getting used to it because it increases your quality of life) and a chemical addiction.
> The chemical/psychological distinction is hardly important.
There is a huge difference. If you are addicted to something it is pretty much a physiological effect on you.
Most physiological addictions have a psychological component. As an example, I'm addicted to caffeine, but I'm also dependent on coffee as part of a morning routine. Smokers who are addicted to nicotine are often also dependent on the social aspects of being a smoker. It's often the psychological component that, long term, is the hardest to break.
The converse, however, is not true. A good example is so-called "Internet addiction" which should rightfully be called "Internet dependence", at best, because it has no physiological component.
Simple example, the addiction of the adrenaline rush and dopamine release of extreme sports.
Smoking is expensive, unhealthy, inconvenient, and stinky. That's why there's a big push to get people unaddicted to smoking, but not so much push to get people unaddicted from caffeine.
Honestly, I liked smoking a lot (still do really). I disliked the addiction.
"Quit Smoking the Easy Way" by Alan Carr