I can't think of one single movie with an energy theme that didn't have some sort of political issue or corruption play a major part. Energy is always portrayed as a means for wealth, and the wealth in turn, turns major stakeholders either completely beserk (There will be blood), corrupt (The company being sued Erin Brockovich and just about everyone on the TV show Dallas, if I remember accurately) or both (There will be blood & Dallas). I don't remember beverly hillbillies too well, but if there was no corruption or craziness in that show, it's probably because it was a comedy.
As they say, art imitates life, so I have no problems with the truth being conveyed in the movies. If there is anything that we should learn from these movies, is that ethical responsibility will forever be a part of our legacy. At any point down the road in our lives, when we are faced with making decisions that will forever define us; I hope we all remember that the truth will always be revealed, especially in the United States (not so much in my home country, Nigeria, but Godwilling we will reach that level of freedom of speech/ information someday).
Another thing about America, is that if the story is sensational enough, or if the subject was rich, and powerful enough, a movie/TV show/documentary/book will be based on the story and the subject will forever be linked to the scandal, regardless of the rest of the subject's life.