I really don't have a problem with people being greedy. And, from what I know of it, most of Blackwater's operators are each independent contractors and not "employees". Each works on a 10-99 basis and pays his own taxes, FICA, etc. I understand some operators made $20k per month. Sounds good, when you're warm, dry, clean, fed, and no body is shooting at you. Take that away and $20k / month doesn't sound so appetizing to me. I don't think their compensation was excessive given the task, and potential cost. I don't think their compensation was tax free (but I really don't know one way or another.) Its tough to trust (a) people when you know that some of them are capable of the savagery on display in Fallujah. It would make me adopt the "Kill 'em all. Let God sort 'em out." mind set.
Personally, I have to admit that I have a problem with greed when it causes people to put themselves into extremely dangerous situations--like Blackwater in Iraq who then gets themselves killed as a result of (1) underestimating enemy strength, (2) underestimating the mind set of the enemy, and (3) getting themselves killed as a result of their greed which then leads to the US screaming for blood and revenge against the insurgents.