I figured this line covered that, more or less: “A quick perusal of an ekrat’s lair may turn up any number of scrolls, maps with magical writings, spellbooks, and more unique types of magical tomes or manuals.”
I guess it would. Leave it up to the DM, rather than random chance, to determine if that tome of understanding +3 is in the lair of a 1 HD fey. I like it.