A lot of people cannot get a good night of sleep because they have to wake up super fucking early in order to arrive at their work on time. A number of them might then go from work straight to classes (like a cheap college-level graduation, in hopes of getting a better paying job sometime in the future), so by the time they get home, their free time is spent caring for the home and prepping for tomorrow. Even those that have "free nights" may not end up spending that time for leisure

Birds singing are rare in big cities. You know, the so called concrete jungles? They'll have a number of pigeons and sparrows, but depending on the city, the lack of trees means that's the only 2 kinds of birds you'll see or hear, period.