It's called boycotting and it's perfectly legitimate.
Like saying, I don't want anything by Ray Bradbury or wossname who hates computers and thinks geeks are subhuman.
As a kind of reverse situation, I quite liked Battlefield Earth and the Mission Earth Decalogy[1], by L. Ron Hubbard.
This was back in the early '80s, before I'd even heard of his church. (As far as I was concerned, and I suppose I still am, they were "rollocking good reads", in a Sci-Fi-schlock kind of way. Some rather perverse imagery[2], and some rather silly premises[3][4], but the books worked, in their own fashion.
Less than a decade later (once I knew about L. Ron's more 'pastoral' output), I probably wouldn't have touched his works with a bargepole, such were the bad opinions of his organisation on Usenet/etc... OTOH, by having read the books I also know that had I
not read them my life would have been not much poorer, either. And I'd have probably just read something else instead[5], possibly to my benefit.
Still, while there are all kinds of reasons to avoid books, I think "book-burning Mein Campf, even for the irony" isn't something you should be tempted to do... And authors' opinions can be easily ignored (the Christian imagery in the Narnia series, for one, or the quite modern anti-sexist ironic style employed by Edwin Abbott Abbott in his Flatterland book as something that's actually (when you realise what he's doing) a
palatable subversion of the contemporary societal condition), and I never put books down (unfinished) for
that reason...
As for not picking them up... You makes your choices. Obviously if you're buying the books you're going to have a standard compatible with "do I really need to waste my money on this?" if it's of an iffy heritage, whilst borrowing from a library lets one extend one's range a little more beyond the paid-for limit of how far you'd go beyond your comfort zone... And regret it less if what you pick up is distasteful/boring/badly-written/whatever and you realise your mistake.
[1] Or however he spelt that word...
[2] e.g. Mission Earth's "plastic surgeon" alien who had some rather strange proclivities as to the plastic surgery he'd perform, and the Earth-girl hooker who got kidnapped and ended up teaching the alien catamites how to be... interesting... But as I doubt you've read the whole ten books in the set (makes LOTR almost look like a pamphlet...), I suppose "you really have to have been there" to understand...
[3] More so for the Decalagy/Decology/whatever, where immediately prior to the forward by the Alien Minister Of Literature saying as how Earth is a fictional place is the forward by the Alien-to-English
translation robot who starts to question not just why he's being asked to translate the book into the fictional language of English, but if the Earth and the English language are fictional then
why/how does he (the robot) even exist?
[4] Battlefield Earth was much less silly than the movie. I could 'believe' the book, but the film stunk.
[5] I think, at the time, I was reading through the library shelves in alphabetical order of author. Thus someone with a post-H initial would have benefited from my attention I suspect. Zelazny, mayhap...