Could be a learned trait, or could be ingrained in people's psyche. Either way, to me, greed is as heinous as it gets.
Today, President Obama and VP Biden lashed out at bank CEO's, who paid themselves $18.4 billion in bonuses; just as hundreds of billions of US tax dollars are going into saving these banks. Obama called it "Shameful" and I agree. Biden said he would like to put them in "the brig". There's an old saying: "beauty is only skin deep, but ugly cuts straight to the bone". In my opinion, Greed is the culprit that's turned our world economy into a black hole.
Oversight + accountability= Keeping people honest