There could be many reasons. I'm not a night owl but for some reasons I prefer to stay awake at night like doing web project, writing influencing content etc.
Normally people loved to awake at night in the cities for not any reason because they are habitual of its routine. They can't change this habit. They are just wasting their time by watching movies and hang out with friends.
Many of us working online so we all have need to awake at night for earning some handsome amount to feed our tummy. Some people are writer who needs peaceful environment that's why they prefer night silent.
Though its bad to awake at night as per doctors recommendations. They warned you not to stay active at night if you want good health for a longer run. I believe that staying awake at 10 to 2PM is harmful for our health.
Health should be top priority so becoming a night owl may damage our internal health silently. I only awake when it is needed.