I think it quite obvious that this is nothing more than revenue enhancement.
I think you're right. Here in Washington, they're always coming up with a new scam to shakedown the public. Recently, it was cops posing as panhandlers on the side of the road. If anyone stopped that wasn't wearing a seatbelt, they'd radio it in to the squad car down the road. After being pulled over, the driver would be slapped with a $100 ticket "for their own good". Of course, the majority of the folks in Seattle are nanny-staters and absolutely LOVE the "Click it or ticket" campaign. I LOATHE NANNY-STATERS.
You are of course quite correct. State and local governments have quite the tradition of unjust revenue-generation methods at the expense of innocent citizens.