I grew up in the US in the 80s and 90s, where we were bombarded with anti-smoking ads, the health effects were well known, and the prices were high.
It blows my mind that I have peers who smoke. They would have seen the same ads, had the same facts available, and mostly come from similar backgrounds (middle-class).
- https://en.wikipedia.org/wiki/Rat_Park
Or in comic form:
Nicotine is a stimulant that elevates the mood almost like magic.
The numbers are particularly telling if you look at schizophrenia sufferers. People with schizophrenia are about 2.5 time more likely to smoke than people without.
While most of these are far less severe than smoking (perhaps obesity, drinking give it a run for its money), all of them are bad for our health in the long term and we know it, but we do it anyway. There's plenty of information out there to know about it, it's not like people don't know alcohol or burger king is bad for you. So why do people do it?
When you answer that question you'll have the answer to your question.
A lot of especially young people just plain do not care what happens to them when they are 70.
-- Norm Macdonald
You've answered your own question: rebellion.
That was the main reason I was sneaking cigs in the alley after school.
Just ads, ads and ads. That generates a tobacco culture with smokers and non-smokers, but both just saw ads.
Because tobacco smells and tastes nice (cigarettes mostly don't, but cigarettes are to the tobacco world as McDonald's is to the hamburger world). It stems the appetite and heightens the mind.
Why don't more people start to smoke?
Plus, smoking a cigarette feels really good. Once you're addicted, they don't, but until then they just feel really nice.
Behaviors are "contagious" that way. Gun violence and suicide have been shown to be "transferrable".