When I lived in Palo Alto CA I had to have - or was supposed to have - a bicycle license. It cost a few bucks and you got a sticker for the bike. I was told it allowed the authorities to more easily return a bike to its owner if it got stolen. I got two licenses and was irritated with the sticker as I do not like stickers! My problem. But I put it on my Mondia and my daughters GT. The GT got stolen the first time and the police did not find it, some kids recognized it outside a supermarket and corralled the thief and took the bike back. Then it got stolen again and someone found it in some bushes, recognized it, and returned it to my my daughter. Then it got stolen a third time and, as is said, three time's the charm! We never saw it again.
At no time was the license of any use at all.
My Campy still has the silly thing stuck on it I think, unless it fell off.
I live in Bethesda, outside of DC. I commute through DC to Virginia. No one here requires anything so silly!