Well, to be fair, you decked your moto-bike out to look just like a full blown motorcycle. He probably didn't even realize it until he had already walked up and saw it. He was probably trying to save face....in that weird, pig-Nazi way.
It seems that everyone who just slaps a china girl onto a normal looking bike gets away with it...and people who deck out their bikes until they are almost unrecognizable get pinched. Just sayin.
The cop didn't care about the actual law, he was just being a bully because he thought you were flamboyantly flouting the motorcycle rules. IMO, from what you posted. I agree with others...slap some lights and reflectors on it if you're going to ride a WWII bicycle thing.