PS, and @mwalsh9152
knows this is true, when I was working at a friends gas station on Saturday mornings,and between gigs, I inspected cars for the most part.
I could bang 8 to 10 cars an hour thru my bay even with the emissions tests and I checked everything.
I rejected cars for side marker lights and plate lights all the time
I'd reject it, put the R sticker on, and then give the person the option of putting one in themselves, or I would do it for a couple of bucks and the cost of the bulb. I wasn't making any great amount of money selling light bulbs for a couple of bucks, but it gave me one of the highest rejection rates in the state, on paper, and that allowed me to fly under the radar on other things I would let slide as long as it wasn't a safety issue.
Some people bitched, but I had on the bulletin board next to the drivers window newspaper clippings from the local paper of all sorts of people getting arrested for this and that, with the probable cause starting with a side marker or license plate light being out.
These days, LED lights have reduced the number of failed lights to near zero, but when they do fail it is a royal PITA to replace a bulb.... you should not have to remove the front bumper or half the engine bay to get a side marker light into the housing but it happens every day, and license plate lights are not any easier