Sometimes people should not ignore the elementary function of those financial products. Most of them are originated for hedging, not for "pure" trading, just the same as those futures and forward contracts.
Therefore, Goldman Sachs itself is not the origin of the problem. It's the regulations, those regulators should be blamed. But unfortunately politics will inevitably involved about this issue. You can not prevent people from being greed, things you can do is how to rein in the greedy of those greed people.