At least where I am in Northwest Ohio USA there are a lot of companies that do not allow smokers to work for them, and that means a nic test on employment and probably on occasion.
This is directly because the insurance companies charge more for smokers, and the company employing them has to pay more for the smokers insurance, or they get a better group rate for the company.
I don't get a nic test where I work, but if I am on the company insurance plan (I am) I have to declare myself a smoker or take a nic test to prove I am not. Vaping is considered tobacco use in the U.S. As a smoker (I'm not) I get a hefty tobacco Surcharge along with my standard insurance bill, about triple for me what it is for a non smoker.
Ohio is an "At will work state". You agree to your employers rules if you want to be employed by them, and it's your choice to stay there. The rules are always subject to change without notice.
Hospitals, some automotive industry factories, our casino does not employ smokers, it's a business move to cut cost.