The argument that cars and garbage are just as bad isn't valid. Cars and garbage certainly aren't necessary in any existential sense, so don't even bother trying that angle, but they're necessary for modern life. Cigarettes aren't necessary for anything. They quite literally have no functional purpose, which is why they're shit-like stink can't be categorized with other stuff that creates stink while also having purpose.
FWIW, I would vote for a law that outlawed perfume and cologne just as I would cigarette smoke.
It's not an invasion of privacy for someone to ask you a question on a job application. You don't have to answer it and they don't have to hire you. I don't hire smokers and there are many perfectly valid reasons for that. I also don't hire other groups of people for which I, too, have perfectly valid reasons. Don't get addicted to stupid shit if you don't want to face these kinds of issues or simply learn to accept that you made a choice and there are consequences. Yes, there are consequences to many other types of self-indulgent behavior that are trivialized more than smoking, but that doesn't mean smoking should be ignored. If anything, it means we should probably cast a broader net.