Personally, I think corporations are often evil regardless of the "direct" actions of their leaders or employees. Sometimes all it takes is for individuals to simply do their job well.
In large groups of highly specialized workers, it can be very difficult for individuals to see beyond their specific role in an organization, meaning that the problem of evil is inherent in the byzantine hierarchy itself and not in the specific actions of its individual constituents.
I'm very tired right now and I'm not sured I explained that well, but hopefully someone will understand what I mean...
I think of corporations as amoral: not necessarily evil, just not caring.
"Experience has proved that some people indeed know everything." -- Russell Baker