Excrement occurs
You might want to reread my message, or read a later version with some editorial revisions. I made a point of stressing that this has nothing whatsoever to do with the question of correct color. It's a question of whether NASA's images can even be called color, strictly speaking.
What would be the point? There is no point, as I said in a message down the thread in which I speculated about the cause (and a cause is not the same as an intention). Call it an emergant phenomenon of bureaucracy. Shit happens. Especially in bureaucracies.