Yeah for sure... I just spent about 25 hours in a single weekend coding on my own stuff. And I feel great now. I had that high today, on a Monday! But even though games are somewhat interesting, it wasn't my main passion and I wasn't that good at it, so I got burned out pretty fast.
So bottom line is that it's futile for management to push people that hard. Some people love the problem and they'll put tremendous hours int oit. But you can't force that upon anyone.
On the other hand, perversely, I can see the logic to it. There are 20% of people who are running full stream and being super productive for 14 hours a day. Maybe you just keep everybody in the office so that those people feel like everyone is making a sacrifice too? If you don't care about burning people out, I guess it is rational to keep people in the office if only 20% of people get more work done, if those 20% would leave if everyone wasn't there.