Before I retired I had to get up at 4:30am to be at work by 6am. I don't do that anymore, but still am up by 7am or so.
I am an early-riser on cruises though, and usually out of the cabin by 5:30am. I like to see the sun rise and the ship come to life.
Like Rich does, I end up in the buffet before they open the serving lines to have coffee and sweet rolls. I'll do that on debarkation morning too, but then it's off to the dining room for the main meal.
I still eat breakfast in the buffet on the sea days. But as Rick said, port days can make the buffet a train wreck so we use the dining room on those days too.