There have always been groups of people who have banded together to deny others of their rights. It matters not if they are doing for the same reasons as others.
Groups of resturant owners acting to squash competition by using government to deny rights are every bit as evil as those who would do it for other reasons.
Thats majority rule. Unless smoking were specifically protected by the constitution like guns, the press, speech, religion etc then its perfectly alright for the majority to ban it.