Your interpretation is wrong, I've been to Uber's office in SF and its dinners are big trays of catered food brought in late in the evening. They're dumped in the kitchens and employees who are still working can come by to get whatever they want.
Also there's no concept of overtime with salaried fulltime employees. You might work 100 hours in a week and you're still taking home the same paycheck as if you worked 40 hours. That's just the way corporate America works.
I work 6am-10pm one day a week voluntarily, though I work for myself. I avoid traffic, parking is easier, and I get the office to myself without distractions for about 6 hours.