80 hours a week doesn't mean they are doing nonstop nitty gritty work 80 hours a week. They could be spending large portions of that time in the tv room watching movies or going to fancy restaurants for 4 hour lunches.
I on the other hand was THE pediatrician for over 20 births last night (I now officially hallucinate babies

) and my decisions could have meant killing a newborn baby child or leaving the little rugrat terribly incapcitated. Imagine if because of physical exhaustion I could have dropped a baby on the floor? For one I could have been kicked out of the internship, the hospital get sued and I could risk going to prison. For over 5 hours I was working nonstop attending births without resting a minute (sometimes atending multiple births at the same time, ick), it's not like the work was all that spaced out either and I also had to attend the ICU unit as well doing notes, drawing blood samples (very hard to do when your patient is smaller than your hand) and ingresation papers which most interns aren't even allowed to do.
I don't see those fed dudes worrying much about going to jail for dropping a few folders filled with papers.