Further Harassing Smokers

Possibly someone could explain the externality from letting people smoke outside the building. This is from the Baltimore Examiner:

BALTIMORE (Map, News) - Banished smokers taking nicotine breaks outside bars in one of Baltimore City’s trendy neighborhoods are being told to move or face fines and arrest for loitering, bar owners said.

Hampden bar owners said they were shocked last week when police began warning patrons to move 150 feet away from the entrance of bars they were patronizing or face loitering charges. . . . .