While walking near a NY police station, I once saw a Charger (maybe?) parked partially blocking an intersection (or a driveway? This was years ago), next to a hydrant. Someone was using a white paint pen to write "COP CAR" on the side. Another cop in uniform came walking up, looked at what was happening, and then told the graffiti artist, "c'mon man... Finish it quickly and get out of here before I see anything."

I was about to take a picture of the scene when the cop put his hand up and gave me the only good advice I've heard from a cop: Don't ever take a picture of something that isn't happening.

As soon as the guy finished and capped his paint pen, the two stood near each other for a moment, and the cop said, "he shouldn't have parked there. Shame he didn't listen to any of us. Well, I guess I gotta report it; I just wish I'd gotten here in time to catch whoever did this."

This video by Benn Jordan explains how to do it

Main result I'm getting is alitelabs. They don't explain what "nano" means, so I assume it just means a very fine grain reflector pattern to make sure it blends correctly.

I'm more interested in the random dot pattern that somehow fools text recognition software. Just little artifacts around the plate. I don't trust not being hassled by cops with reflective letter decals because they'll be visible, I'm sure. It's not so obvious, but your headlights align with your eyesight and reflect off license plates because cars have license plate lights. It's really obvious when you have that knowledge, pull up behind a white/pale reflective plate, and have a mismatch of light color between your headlights and their plate lights - namely one with classic warm white incandescent, one with typical modern cool white LEDs.

The general public who are aware do care. It's the institutions responsible for enforcement that don't care. A member of the general public can't issue a citation.

It's called Parking Enforcement and New York City has more than any other jurisdiction.