I think a lot of the problem is that Games Developers themselves don't do enough to prevent this. This certainly doesn't excuse the managers who take advantage this way, but if more developers were confident enough to take a stand, they'd have more success changing this.

Pachter said. “I’ve never heard a developer say ‘I don’t work overtime and I don’t work weekends’. Well, at my last industry job, that was me. I never worked weekends, and I only worked evenings if I had fallen behind myself on what I planned to get done. I made it clear to my managers (in a non-confrontational way) that overtime was not to be 'expected', and that I would only work extra hours in extreme circumstances if we had immediate (read: in the next 1-2 days) deadlines that my planned work was not going to be ready for.

My managers were pretty ok with that actually - I was still a good programmer and put plenty of effort in during my normal work hours, and it meant that people had an accurate idea of how much work I could normally get done in a work week.