The rules are that, only people who have seen every movie can vote... so Sony doesn't let people other than those they select, see their movie, leaving only people in their camp rigged to vote in their movie.
It is extremely dishonest, and corrupt. The concept of not showing a product, in order for a product to win an award is an example of Sony being a jackass.
If they feel their movie is better than Michael Moore's, they need to let the academy members see it, and decide for themselves.
Moore's movie was full of half truths, naked lies, etc... but he should have the right to a level playing field all the same. Sony should be ashamed of themselves.