It's tough to compare these
Yes, but necessary, IMO.
How do you quantify the greed of mankind?
There is a theoretical framework for this called the "Price of Anarchy"; it was introduced by some theoretical computer scientists about 20 years ago and it's attracted quite a following among the engineer/computery game theorists out there. Essentially, it tries to measure just that - how do you measure the harm of greed?
For the past couple years I've been studying the price of anarchy in some network routing systems, and I agree with you that it's a hard problem - but I think it's an interesting and important one nonetheless.