The people defacing artwork reminded me of this story.
My mother used to work in a small religious college. We were good friends with the librarian, and occasionally helped out in the library, especially at the end of summer when they were gearing up for the fall semester.
One summer, we noticed that we were putting away a lot of brand-new, newly-cataloged art books. Someone commented to the librarian that the art department must have gotten a new donor, to be able to afford so many large, beautiful, expensive books on art and art history. Oh no, she said, she had to budget for these books every two years, because she had to replace them so regularly.
It seems that some of the students were from a sub-group of this religion that taught them very firmly, from a very young age, that human bodies were bad and evil and lustful, and that nekkidness in all its forms was a sin. Imagine their shock when they got to college and discovered entire BOOKS with pictures of paintings and sculptures of people's bodies! Without even a fig leaf or a tactfully placed scarf, sometimes! They couldn't just put the books down- that would be encouraging other people to sin, too! So sometimes they would steal the entire book. Sometimes they would just rip out the pages that had the horrible photos. And sometime they would cut the horrible photos out of the pages, leaving the written text behind.
The favorite, however, was the person who carefully and painstakingly used wrapping paper to make paper-doll outfits, and clothed each and every one of the nudes.