This is why we need Public Interest Capitalism:

Markets can only function well if there is an appropriate legal framework to restrict the behavior of market participants; however, the legal framework is inevitably inadequate. A “greedy” market participant that seeks to gain at the expense of others can usually findsome way to do so.

http://www.academia.edu/1434169/Self-interest_vs._Greed_and_the_Limitations_of_the_Invisible_Hand