Actually, they are. So says
the Supreme Court of the United States in upholding the Police Power of the States to set and enforce local zoning, or to divest some portion of that power to entities of their creation - local counties and municipalities.
Your view of history and what people would have done is ahistorical. I will however agree that history has demonstrated that starving populations do tend to attempt to overthrow their governance with unusual frequency.
SCotUS says its Constitutional - see my first response.