Because our brainless boss parties while we work
In my experience, the middle managers were more miserable than the peons. When I became a manager, I hated it.
Only the tippy-top managers really seemed to like their job, and they tended to use the company dime for most of their frou-frou.
That said, I very much enjoy not working for big companies, anymore.
Is there political corruption and abuse that keeps you there?