ahhh, never thought of that problem. I've always thought the idea behind rear fog lights was a good one. But I could see that happening a lot, especially when so many drivers seem to think lights are a decorative item on cars:
They are great when they are on all the time and purple
Then there's those that aim their fog lights as high as they will go because "they don't light up far enough down the road" and then drive with them on all the time.
Or my favorite, tinting taillights; because, I guess, it is so annoying being able to clearly see brake lights in the bight sun. And there's no real reason for lights on the back of a car.