This point is made in that book I mentioned above.I have no idea if there's any validity to this, but when my ex and I were buying a house in a new neighborhood that had a list of HOA requirements (no cost to the HOA, though), we asked the Realtor (who was also one of the investors in this neighborhood) what would happen if someone in the neighborhood broke the "rules." He said that if no one complained, after a certain period of time, it would make that rule null and void. If you've had chickens for 5 years and no one has complained until now, maybe there's some loophole there.