Whats the difference? I own my restaurant, I let people come in to be there, you don't like the rules you can leave and go somewhere else, its that simple. Tobacco is not an illegal substance and as a private establishment I should be able to set the rules in my own place.
You can set some rules, and not others.
You should be able to put up lava lamps or chandeliers, shag rug or wood floors, serve burgers or tofu.
You should not be able to create an unsafe workplace for workers, and their 'right ro leave' does not give you the right to create an unsafe workplace.
In the late 19th century, when workers were paid barely enough to get food to eat and the public was angry, an ideology spread in the country that "contracts" were the fair solution. They could still pay the same low wages, but by having the worker sign a contract for that wage, it was said "he didn't have to sign, it's a mutually agreed deal and therefore fair".
It took some time for public opinion to evolve to say there was an inherent power imbalance between the employer and employee so that a contract did not make it fair.
The worker has to eat - and this allowed employers to push their wages down and down to where they could sign to work for almost nothing or starve.
There was no 'invisible hand' or 'free market' benefits fixing this - it was just a disaster for the workers.
This is where a recognition of the need to even things a bit on power came up, and the right for workers to organize got support - and it worked.
An employer could tell each worker, 'sign or starve', but if it told that to all its workers, they could say 'you can't afford for the workforce to strike' over poverty wages'.
This 'they can leave if they don't like getting cancer' line is like the 'sign the contract for poverty wages or starve' line. It's ridiculous, and it's wrong morally.
There are people who still think segregation should be legal because they take the 'private business' ideology too far, and would let segregation come back.
Businesses do not need to be allowed to do things against the public interest, like segregate or create unsafe workplaces.
You are a sad person to put your 'freedom' to give people cancer ahead of the health of workers. And you're wrong.