But the work is fundamentally different. You can work 80 hours in retail for example. With Uber drivers it's not "drive down long stretch of road without a break for 8 hours".
Uber drivers are, well, drivers. I wouldn't trust somebody working 80-hour schedule (with everything that implies about their quality of rest, or lack thereof) to be regularly driving a car in public. That's just accidents waiting to happen.
No one should be doing 80 hours a week, that's 12 hours each day without weekends + commute (1 hour) + 8 hours sleep, 2 hours for eating and you have 1 hour left for the "all the other things". And thats if you don't have children. If you do you already spending more than 24 hours a day.