In my case it was the word 'abridged' that grated (and then the rest of it). I am such a snob. No, I don't really expect ten-year-olds to read the whole of - hang about; most of the books in the boys' section, but I would expect them to be able to read all the books in the girls' section.

Why are the girls' books actual children's books and the boys' books truncated adult reads?

(This is largely a rhetorical question, as it only hit me as I was typing, but if you have any theories ...)