http://en.wikipedia.org/wiki/Green_River_Ordinance
“The name Green River Ordinance is given to a common United States city ordinance prohibiting door-to-door solicitation. Under such an ordinance, it is illegal for any business to sell their items door-to-door without express permission from the household beforehand. Some versions prohibit all organizations, including non-profit charitable, political, and religious groups, from soliciting or canvassing any household that makes it clear, in writing, that it does not want such solicitations (generally with a “No Trespassing” or “No Solicitations” sign posted.)
The ordinance is named for the city of Green River, Wyoming, which in 1931 was the first city to enact it.[1] The ordinance was unsuccessfully challenged on constitutional grounds by the Fuller Brush Company in 1932.[2]
The ordinance has been challenged before the Supreme Court on several occasions.”
And you like laws like that?