Anyone who flys east west over Arizona regularly as a commercial passenger sees a major north south highway every flight from 25k. You also see cars and trucks driving down that highway during the day. Because it's a major flyway, you also see private planes and jets go by miles away and thousands of feet below. Unless they are painted black or dark blue, they always stand out in white and other bright colors. Sunlight is amazing stuff when it interacts with 3D objects and bright color.
In the game on occasion, fighters in bare aluminum will stand out way past 6k and even sparkle in the sun. But, most of our fighters and bombers are painted in dark none reflective colors. And like I said above. Black, brown, green, gray, and dark blue doesn't stand out like white and bright colors at a distance because of how sunlight interacts with them.
A vehicle sitting still against terrain color and clutter painted in similar colors will be hard to pick out.
