The notion that working long hours and not taking holidays makes for a more productive workforce is, in my view, a managerial myth, with no foundation in organizational or psychological science.
Regardless of the drivers of these behaviors, all agree that with sufficient awareness and a healthier view of our own personal power, this form of psychological warfare can be controlled, if not eliminated.
Either we must conclude that even ants are capable of such empathic suffering, which seems absurd, or we must view the rat experiments as proving nothing about psychological motivation, leaving human beings on a pedestal.