I manage full-time contractors who can work any hours they choose and have an endless stream of work. Many of them are paid 4-5x average pay for their countries. I've noticed that most of them end up working 30 hrs/week. They're required to stop tracking time for every break, verified by cam/screen shots. Additionally, many end up taking on a second job. I wonder if that's because they can extend their productivity by doing completely different things.