I somehow feel that when your company is growing 1000% a week and you have lot of equity in that company, somehow you find strength to work that many hours without breaking sweat. I believe thats more enjoyable experience than just work.
Where "somehow you find strength to work that many hours" actually means "somehow you find self-deception to blind yourself to the fact that you're harming your company, not helping it". If you came into work every day drunk, would you expect to be lauded as a hero or would you expect to get a warning followed rapidly by dismissal? Working excessive hours has about the same effect on your judgment, and should be treated the same way.
but would you have the self discipline to recognise when long hours are becoming counter-productive, and being harmful not helpful?