I think hiding him on a nice farm where roosters are allowed is a good idea. That way he can crow to his heart's content and maybe have a nice little harem of hens, too. Those collars that restrict their crowing restrict it by limiting their air flow. They can also cause a rooster to choke on food if it gets bits that are too big to go past the collar. Inhumane, in my opinion. There are those who have successfully used it, and others who have accidentally choked their roosters to death with those collars.
How did you end up with this cockerel? Did he come from a feed store bin that supposedly had pullets? If so, maybe they'd take him back. Put an ad on Craig's list or in your local shopper paper if you have one. The problem with sneaking one under the wire is, if you are caught you will have to get rid of it anyway. You could also be jeopardizing your right and those of others to have chickens at all. The city may want to change the laws to not allow any chickens at all because of the people who wish to break the rules.