It was me that it happened to, when Keith found out the statute I relayed it to the officer and he told me that i was wasteing his time and as he was a highway patrol office i was not to question his judgement. He effectivly told us to leave the state asap or be fined for no licenceplates. we had all relevent data. effictivly i believe the guy was a tosser!
Politely ask the office to write you a ticket and tell him that you will see him in court, to let a judge decide.
It happen to a buddy of mine and the judge told the cop that in fact he was wrong.