When I was in college getting my graphic design degree, I experienced the situation where you know you are more talented than your professor and they kind of resent you for it. Even though you are putting out better work than anyone in the class, they tend to be more critical and discouraging than anything else. However, I would like to think that an accomplished, award-winning motion picture artist would be a little bit more professional than some old lady stuck teaching at a community college. Then again, it is human nature.
But it's also possible that the judges are just a victim of editing. My boss has starred on 3 reality shows as of now and has a fourth in development and he explained it like this: You can spend 55 minutes singing another person's praises and talking about how good and talented they are, then 5 minutes giving constructive criticism and outlining how they can improve and the editors will home in on the 5 minutes of criticism because it's seen as more dramatic. The editors decide what story they want to tell first, then they pick and choose, from the hundreds of hours worth of footage, in order to create that story. Documenting what "really happened" is not really that important.