kids books?
You're talking to someone for whom
Foundation, Lord of the Rings, and
Song of Fire and Ice (the first one or two, anyway) were "kids books" - books
I read as a kid, anyway - so I don't really appreciate the distinction. Kids aren't idiots and writing for them isn't an excuse to be half-assed.
If kids can play Pokemon they can handle an elucidated, rigorous magical system. Haven't you ever seen a ten-year-old talk about dinosaurs? I could have had a master's degree in paleontology when I was 12. Now I can't even remember the difference between
brachiosaurus and
diplodocus.
it's really not that important, i don't think.
It didn't really hamper my enjoyment of the book, it just gave me some "uh, what about..." moments. Clearly, though, it's enough of an issue that some people didn't enjoy the work. I assure you, not liking Harry Potter isn't an indicator of being a soulless automaton - it's an indicator that one likes a great deal of rigor in one's magic.