I once lived in a place with pretty severe chicken restrictions: No more than 3, written permission from everyone within 100 yards, prooperty line placement restrictions and no roosters, which were illegal within the city limits. I had the blessings of all nearby neighbors, the Zoning folks, Animal Control....and then one person 99 yards away nixed the project out of spite.
THEN my next-door neighbors got an Easter chick for his kids which grew into a roo whose coop was located 15 feet from where I lay my head at night. Sure, put it in the backyard next to the property wall where no one will see it. They couldn't hear the thing because their bedrooms were on the far side of the property. The kicker is the thing would crow and crow and crow and all the nearby neighbors would give *me* dirty looks thinking I was keeping a forbidden roo. After all, I was the registered and petitioned chicken keeper. Anyway, after a full moon and a night of incessant cockadoodling the bird had to go.
So, yes, I can definitely understand the why of "No Rooster" ordinances, especially in areas with population densities. They are louder than you think.