Because a LOT of it is blacked out! These are areas with pure black in the pixel. This is the AS17-147-22590HR version linked to by Skippers report 204. My guess is that there is something behind them thar hills or just that they do that with any areas blacker than a certain grey level.
It is said..... (although I am not sure whether I believe it)
On the Moon, there is not supposed to be any 'weathering' processes as there is no water, wind, or freeze/thaw erosion systems. and so this would mean a geological fault in the rock underneath would not erode nearly as quickly as one on Earth would.
I have seen these moon hills before and wondered about them. How they look very regular.
Mission 17 was a bit of a strange one I think, since they took the geologist guy and there is a large question mark over some of the things they said and supposedly found. There's another thread on Apollo 17, but this is a different issue.
If there are Moonies up there, then they would have signs of their culture left all about the area just through normal day-to-day living.
When I was a studying J.P. Skippers Report 204, I noticed how all the lines of the landscape on the image was symmetric. Notice how all the lines are straight and parallel with each other, specifically outline and internal lines of the rock. This raised my suspicion that maybe some secret information was written in the form of rock, forced me to examine it more closely her is the result. This is a realistic outcome, if we have in mind, aliens, and symbolic meaning.