Group Psychology and Herd Instincts

Rod Dreher reflects on a conversation with a former investment banker:

I had a fascinating conversation this evening at an event. My interlocutor was N., who had left a Wall Street job as a trader to focus on family. N. is a serious Catholic, and told me that working on Wall Street was a constant challenge to one’s faith and to one’s sense of morality. I asked for an explanation. N. said that there was so much money (and therefore power) sloshing around the Street that it was very, very difficult to keep your head on straight, and not to lose perspective.
“It’s like a cult, being at the investment banks,” N. said. “You come there straight out of college, and from the beginning you’re rolling in money. The salaries are great, you get to stay in the best hotels when you travel, they take you out to the most amazing bars in Manhattan. One year they hired [A-list movie star/comedian] to perform at a private function for us.”
“It’s so amazing that before long, you don’t want to do anything to upset the status quo,” N. continued. N. said that the herd instinct takes over, and pretty soon everybody is starting to see their purpose in life, both professional and personally, as doing whatever it takes to preserve these privileges. N. dwelled on how shocking it was to observe how much emotions and group psychology — not objective analysis — drove decision-making. Going along to get along. Everybody was making money, N. said, which the cult of Wall Street believes is a sign that its devotees must be doing something right under heaven.

Wasn't The Firm just a dystopian version of this?  I read that book almost 20 years ago in college.  It isn't too hard to understand how this works.  You get comfortable in a certain lifestyle, and your dependence on your income to maintain the status and connections means you can't rock the boat or question your bosses.  All social structures work this way, some good, some bad.  What keeps people from breaking social mores against adultery or theft?  But also, what keeps decent people from standing up against bigotry and racism?