We’re fucking exhausted and there’s never an end to work (agile). That’s probably part of it.
At least when I worked in fast food, sure there'd be the nightly dinner rush, but that only lasted about two hours, then everything would quiet down and you'd get to take a breather, take your time, goof off with coworkers, put a movie in the VCR in the breakroom (it was a long time ago), etc.
Usually I at least take it a little easy the day we finish a sprint, but I still have to 'report what I did yesterday' in the sprint meeting the day after, so I have to have done enough to have some progress to report the next day. And then it's off to the races again. It's fucking exhausting.