At night, not many people really enjoy lying in bed. It's generally felt to be a waste of time to lie in bed awake for too long at night. It's been a long day, you want to get to sleep as soon as possible. In the morning however, lying in bed is a luxurious feeling, that you try to stretch out as long as possible. Really very enjoyable. Why? I don't really know. Perhaps it's Murphy's Law or something. In the morning, when you don't have time to relax, that's when you feel like relaxing the most.
So what do people do during these downtimes? At least some people apparently use their stomachs as a drum, and drum all morning. This was news to me, as I had never even considered doing this while lying in bed. Many people read. Listen to music. Listen to old radio plays? Some just lie there and think about stuff. Or fantasize about stuff. Morning is just a really good time to hang out, reflect quietly, stuff like that. Just great.