The police pull over anyone they think suspicious. They only need probable cause. Because there are so many traffic laws, it’s easy to find a reason to pull over ANYONE!
Do they really care that your license plate light is out? Of course not, but it is a legitimate reason to pull you over. It opens the door for further investigation. Upon further investigation they find intoxicated drivers, GUNS, DOPE, escaped felons, people with outstanding warrants, stolen cars, stolen property, hookers, johns, unlicensed drivers and on and on.
It’s called police work.
Educate yourselves. Watch a “COPS” marathon on TV (yes I’m totally serious). You will see patterns emerge and get a real understanding of what patrol officers go through on a daily basis. No actors, no scripts, no filters, see it as it happens.
Having a license plate out means if someone, say, hits someone else and runs, or robs someone/someplace, and it’s nighttime, getting their plate as they flee is almost impossible, so it’s a legit concern. Just two examples.
I meant to say, a license plate light out, obviously