But where will it end??????
You don't own that restaurant - if your smoking friends are willing to sit in the non-smoking section why didn't you just go to a non-smoking reataurant?
Your position ignores simple premises of things like private property rights and personal responsibility.
Talk to the owner of the business - don't promote more government intrusion on small business persons.
Not to mention that Miss Manners would be horrified at such boorish behavior.