I'm an ex-smoker as well, and I didn't quit because I didn't like it!! That said though, if I walk by someone who is smoking, I'll take a nice, deep, nostalgic sniff. On the other hand, it now irritates my throat if a space is too enclosed and I'm in it for an extended period of time.
But worse than anything else is perfume! You can tell when someone has been wearing the same brand for too long by how far away you can smell them coming!!