I think an issue here is what you are greedy for. If you check out cats like Jeremy Bentham and J.S. Mill, they talk about everybody seeking to maximize their own utility, being greedy for more of what they hold to be important. But they also talk about how this utility is defined differently by each individual. Some people gain utility from feeding the poor, some from feeling that god is with them, some from love, and unfortunately, some for the pure accumulation of money. Clearly somebody who is greedy for the feeling of satisfaction that comes with feeding the hungry is probably benefiting society, so that their greed cant really be seen as bad. The problem is not the amount of greed that we have, but what we are greedy for.
Peace,
Ovan