On my first RAGBRAI (1978) we overnighted in Maquoketa. As souvenirs, the town handed out some of their outdated bicycle license plates from the previous couple of years (while supplies lasted). I’ve still got mine hanging in the garage.
I think I hung on to the little manila envelope they came in as well, since it indicated that the bicycle license plates, like the larger car license plates, were produced by inmate labor in the Anamosa prison shops.
So there you go — a win-win-win situation. With bicycle registration the cyclist finally gets some official acknowledgment of our rights to the road, the state makes some money, and the prison inmates get a chance to produce something useful besides home-made knives and raisin hooch.