Morality and ethics don't count for anything in a contemporary society where punishment for misdeeds exists only for those who cannot afford to buy their freedom.
You might be interested in post-70s studies concerning the primate theory of mind in this respect. Primates seem naturally programmed to steal but only when they think they can get away with it. I have been following the work of Laurie Santos at Yale on the question of primate theory of mind and her studies of capuchin monkeys. Her work is highly experimental and interesting and she is very engaging.[0]
She set up field studies to test whether primates use knowledge of whether they are being observed to decide when it's ok to steal and it is clear that they do. [1]
When your family is hungry, you will steal so long as you believe you can get away with it and not deprive them further. Primates want to be seen by peers as ethical because it is advantageous (it will be easier to steal in the future) but in reality generally are deceitful at every opportunity.
It seems that we are indeed generally ethical in relations because of cultural discipline/punish power dynamics, not out of any sense of moral duty. I think the only way to rescue Cicero is to discover the underlying mathematical model by which doing the "right" thing and the "advantageous" thing are always the same. If no such model exists, it's just so much hyperbole rambling of parent to child.
There is a scene in the Fifth Element where Gary Oldman knocks a glass off the table to demonstrate how destruction is "good" for the world because it gives all the support actors a chance to play their role. Its a pretty chilling example when you realize that there are people who actually think that way on a daily basis.
I heard a story when visiting London, which may have been completely fabricated, in the context of comparing the morals of banking vs gambling. It told of a book maker who learned that a critical soccer player's girlfriend was planning to commit suicide. Rather than report that information to the authorities to save the girl he used it to bet against the team (the favorite) and won a much bigger return than he would have otherwise when her attempted suicide kept their star from playing. Part of our discussion was whether or not the 'criminal element' which was attracted to gambling (I grew up in Las Vegas just as they were cleaning out the Mafia influence there) was the same or different than the people attracted to Banking. In both contexts 'score keeping' was a simple metric of how much money you had.
If you are an "important person" and someone communicates to you that something is rotten in the bowels of the system and its going to come exploding out in a vile smelly mess. You might ask yourself, "What am I going to do with this information?" What would a gambler do? What would a banker do? What would a politician do?
If you are a TV news conglomerate you might say, "Hmm its one small story of abuse now, but if it really does take out a big chunk of the financial industry its going to be huge! Lets sit on it and plan on how we're going to get big market share from people tuning into us for our indepth coverage!"
If the person getting the information convinces themselves that there is nothing they personally can do to stop it, they can give themselves permission to exploit it (which is usually, but not always, easier). If you can profit handsomely if it happens, and not so much if it doesn't, then what? You see a shark in the water do you yell "Shark!" or do you start recording video thinking about the 10 million YouTube views this will get if you catch it eating someone?
Its Ethics 101. It's why you fire people in your company for even minor ethical violations. It's why you volunteer to run oversight on a local public utilities commission or school board. It's why you go back into the store and return the extra $10 they gave you in change, or pay for product you absently stuck in your pocket and wasn't charged for. It's why you stop interacting with people who aren't ethical.