My car dealer is looking after me. I had one of the Batmobiles in the shop and they spotted that the license plate light bulb was burned out and went ahead and replaced it. I thanked them for doing that. Don't give them an excuse to stop you.
My neighbor is a retired Wash DC detective. All three of his cars have very dark gray plastic covers over the plates where you can barely see the numbers and letters from just 10 feet away.
He never gets stopped.
I believe NC, as well as every state, has a law about license plate obstruction in their V&TL.