When I was a teenager, and in my twenties, I was in a really small minority among my peers in that I didn't smoke. I never minded people smoking around me.
As I have grown older, I have come to not only detest the smell of smoke near (and indeed on!) me, I have come to regard smoking as a ludicrous habit.
It has absolutely no redeeming qualities whatsoever, it smells, it's potentially fatal, and it looks terminally ridiculous.
I am mystified why anyone would take it up in this day and age.