Yes. Montana counties where the majority of voters opposed I-190 can ban recreational cannabis businesses. Cities and counties where the majority of the voters voted in favor of 1-90 can only ban cannabis sales if the voters approve a local initiative or referendum.
For example, the city of Great Falls attempted to ban cannabis businesses through an ordinance despite being in a green county, but a court invalidated the ban, ruling that only voters can prohibit cannabis businesses in those areas.