For set related jobs, the hours are the shoot. If the shoot runs long, everybody's on set. It's an exploitative - and in my view, completely unnecessary - culture. The marriages, parental relationships and health costs cannot be justified by the supposed necessity of dollar savings. But currently - especially in the US, film sets all to often work sweatshop hours. More enlightened practices, like 'French hours' (a ten hour day), are also possible. The films created under these conditions don't seem any worse, and the people involved are inarguably happier and healthier.
