Haven't seen the sun in forever while flying...you just get used to it.

Think about this...during the day, all you see is sunlight and pretty blue when flying on a clear day. At night, especially during a new moon, you can see all the stars, watch meteor showers, see that comet that has grown in size in the past month, lunar eclipses, etc. Not to mention on you can generally see forever...

For me, daytime is just tooo boring.