I work in surveying in King and Snohomish Counties, WA, so I deal regularly with land use issues and regulations. The prevailing governmental attitude here is "We, the Government, know best." Rather than allow people to fan out normally, they designate Urban Growth Areas (UGAs), where high density is allowed. This allows them to keep large amounts of the counties at low density yet regulate what owners there can develop. (Recall the recent regulation in King County prohibiting development on up to 90% of 10+ acre lots.) In the UGAs, houses can be built with as little as 6 feet between foundations, with eaves being much closer. The first time a house fire spreads to burn a whole neighborhood, these idiots might rethink their paternalistic regulations. Maybe.
Zoning laws make little sense.