Here are a couple of reasons which I believe explains the above phenomenon. I'm quite sure those of you who have been in the rat race for a while can think of more reasons.
1. More often than not, management keep these brutal bosses and even promote them because they help push up their bottom line. Those who are subordinate friendly and keep close working relationships with their workmates sometimes are viewed as being too friendly with subordinates and could easily end up as anti-management especially in companies where management are often suspicious of their workers' actions in areas where sick leaves, output shortfall or mistakes are committed and no scapegoats are found to take the blame.
2. As compared to others who may treat work mates or subordinates fairly while dealing with management honestly, these scoundrels would go to work wearing two masks. While they curse and treat workers with spite and scorn, their other face would be smiling and saying 'aye' to management even to the most ridiculous of demands.