The two groups were constructed for the experiment, to emphasize the difference. If you're saying that powerful people in the real world are divided into two groups, that is your own opinion, not something that the study concluded.
What struck me that part of people who have power, those who have high moral standards for themselves (possibly induced by feeling that their power is undeserved) might tend to overlook immoral actions of their peers just because of some glitch in our biology.
I don't have any answers, but found it too interesting not say anything.