> Something about smoking or smokers just drives people a bit crazy.
I think that there must be some sort of human need to have a group to hate, and that in the West today that unlucky group is smokers. One may say the worst things about them in any social or business setting — that they are stupid, filthy, foolish, whatever — without any risk of being contradicted, indeed with the expectation that everyone will agree with you.
When I started at my job, the head of HR noted where the (outdoor, uncovered, across a street) smoking area was, 'but I don't think you're that sort of person.' He'd never have felt free to say that about other behavioural choices.
I suspect that part of it is that smokers were so dominant for so long that those who suffered in the past are enjoying having the upper hand.