I did not intend to imply that those at the "top" were the only ones guilty of greed. it is simply a fact of human nature. the worst offenders are those with political power. they pretend to want to help, but it's all about their own greed for power and other people's money.
As for the matter of Greed... a point of disagreement: Greed is common to all sectors of a society. Not just large corporations. It is more visible there because they can actually materialize that greed, whereas poorer sectors can only hope for the day they'll be greedy too. Failed attempts at Communism and Socialism were exactly a demonstration of how Greed extends to anyone and how Corruption is greed's arm on a society dependent on a central government. But if we look at the poorer societies in the world (and I lived briefly in one) one can see how greed can even manifest itself among those who have very little. It's a harsh lesson I learned in Angola, visiting the poorest neighborhoods and travelling on their crowded taxis that poverty it too generates greed. Greed among family members, among neighbors and among perfect strangers. Greed is everywhere. It's a human condition. One which neither you or I are immune, even if from within the comfortable position of our middle class we are lead to believe we are immune to it. It's not Them that are greedy and Us are not. Greed is us. And we are just like the large corporations. "Them" are instead those rare few humans who are indeed immune to it, who don't share the same gene, and demonstrate so by their actual actions (not words) sacrificing their own well being in the process by dedicating their lives to the others. So, before we look at large corporations at the source of all evil, we better look inside our hearts for that same evil that makes us, the ones who build those oh-so-evil corporations.