George Lucas wanted the original to be more light on the audience (maybe even kids friendly) rather then portraying one of the main characters as a cold blooded killer. Never the less, its one of the reasons we love Han Solo in the original from 1977 - he doesn't take any *brown stuff that bulls drop* from anybody!
Basically, he pulled a Steven Spielberg with all that cash and too few people around him to tell him the truth.
It's a case of George having too many "Yes" people and not enough "Are you sure that's a good idea, sir?" people.