Telling acquaintances who smoked that it was bad for their health stopped being cool about 20 or 30 years ago.
So most people, or at least non-smokers, keep their thoughts to themselves. You know the lungs of that woman who smokes are probably the color of charcoal.
Her lungs are in the process of getting saggy and unable to provide oxygen and remove carbon dioxide.
In a few decades she'll be breathing oxygen through nasal tubes, shuffling around, and coughing.
Not lung cancer, but still a horrible way to die. Like drowning in your own lungs.
But it's not socially acceptable to tell smokers that. First of all, they know. Or they should know. The warnings on cigarette packs are obtuse. However, they're smart enough to read between the lines. Smoking can kill you in a dozen different ways.
Is it a moral duty to remind smokers of that? Someone should. Perhaps a spouse or significant other. It probably seems intrusive coming from a casual friend.
If you saw someone standing on the ramparts of a bridge, thinking about jumping off, would you do anything, or just walk away so he can kill himself?