Actually, there is a subset of humanity that is genetically pre-dispositioned to being awake in nocturnal hours. There is plenty of research out there about it. If you are one of the people who either through conditioning or genetics, happens to be better off on day shift, that's great, but I happen to do better on nights. I would really hate giving up my 3 PM naps. I get cranky and irritable.
On a night shift, I still tend to prefer to sleep shifts, so I usually wake around noon, have a snack, go back to sleep. This allows for me, for example, to do things during the mid-day if needed. I usually get home, shower, have breakfast because breakfast for dinner, nap, snack, chores, errands, back to bed for another couple sleep cycles, then up in time for the roommate to be home, dinner, and off to work after being social.