Yeah, exposing yourself to differing viewpoints is absolutely essential to growth as a person. Being able to embrace the conflict of liking something while disagreeing with its creator is, in my opinion, a key way to embrace the fact that humans are seriously conflicted, complicated creatures.

I can definitely agree with choosing not to do things that will benefit a creator who you feel is reprehensible, though. Not reading books by Card so that his share of the human consciousness is less, and sales of his books are less, is a conscientious decision I can stand behind. But recognizing his problematic nature, and still reading the books, even buying them and endorsing them to friends, is acceptable too, especially if you recommend with the caveats about his views.

I personally wouldn't read Mein Kampf or the Unabomber Manifesto, myself; I don't have any interest in understanding those worldviews, even for the purposes of deconstructing and debating them. I prefer to expose myself to worldviews that I disagree with, but less extremely; For instance, I consider myself a political conservative (though I think I may be finally eschewing the Republican Party) but I discuss politics frequently with liberals. I'm a Christian, but married a Wiccan, and have many friends of various other belief systems. I'm more interested in finding the nuggets of truth and value in belief and value systems that aren't mine, and finding the common ground with people who aren't extremists; That's my problem with TRP, Hitler, the Unabomber and others; While there may be truth and value in their stances, it's overwhelmed by the extremism and the toxic shit; The mental and emotional energy spent in trying to find it is too much, and is better spent finding the value in less extreme beliefs and values.