Here's one more option:
e) People don't think enough about the level of brutality in prisons, and when they do think and talk about it they find it easier to applaud brutality; because anyone who spoke against it "would associate themselves with criminals, with weakness, with distasteful things that people would rather not think about", while speaking in its favor make you look tough on crime.

Given political discussions I've partaken in other forums, I know full well that whenever I condemned prison rape and suggested ways in which it might be reduced/prevented, the typical response was something to the effect of "Why do you love criminals so much?"