One of the predictable consequences of intrusive government land-use regulation is that people come to view the regulations as entitlements. So, when someone builds an innocent treehouse for their children, some neighbor is likely to complain that the treehouse violates city zoning laws.
In New York, neighbors complained when someone built a treehouse less than 40 feet from the property line in a zone requiring 40-foot setbacks. The city said the ordinance applied to any building more than 8 feet tall. The treehouse was less than 8 feet tall, but because it was in a tree the top was more than 8 feet off the ground. If this meant it was 8 feet tall, it was an “accessory building” and required a permit. In this case, the town zoning board ruled (in 1985) that it was not.