I suppose the caveman that wrote genesis didn't realize the sun (created on the 4th day) was required to have "day"(created on the 1st day) and "seed-bearing plants and trees" (created on the 3rd day) because the order is obviously all wrong. Who realized photosynthesis was required at that time? He/They also apparently didn't realize the "lesser light to govern the night" was nothing more than a natural satellite reflecting sunlight.
I could be wrong, but you may be over thinking this. Have you ever believed in something that you cannot fully understand or logically explain?
