You will not get very far with calling people stupid. It takes months sometimes for me to have a glass of beer or wine, and very rarely anything stronger, I don't need it, never liked the feeling of having too much of it.
When I lose my concentration and trying hard to figure something out half a cigarette make my mind work again .. I don't think it is the nicotine though, because vaping with high content of nicotine did nothing other than keeping me from going outside to smoke. I wouldn't generalize though because the effects can be different for different people, even with tea. I can drink 20 cups of coffee a day, and fall asleep with half a cup next to my pillow, I can drink chamomile and some other herbal teas they say they relax and calm you down, and I'll be up all night. Black tea has a higher hit than caffeine for me, maybe my caffeine blood content never drops low enough to notice :)
Smoking became disgusting when the campain against smoking became effective. In previous decades when people smoked more nobody ever called smoking disgusting. We haven't evolved that much since the 70s/80s. So what many people perceive as a disgusting habbit today is the effect of conditioning and propaganda. Smokers also had long lasting relations with non-smokers, now it is unthinkable a smoker and a non-smoker to even go out for a coffee together.
I am also surprised this discussion has gone so far so long and nobody has mentioned sugar and its bi-products (soft drinks, candy, sweets, ...) Is there such an addiction recognized and known as dangerous? Type-B diabetes has become common even for kids, especially in the west. The sweetest thing you will find in China doesn't even taste sweet, and if you offer a middle eastern pastry to a Chinese person they put half a spoon in their mouth and think they are about to die.
Super-Size it PLEASE!!!