It's not for lack of choices- there's a boatload of new fiction all the time. We have so much new fiction in the library- including chapter books for kids. Publishers are hoping they'll hit on the next Harry Potter $$$ or at least one of some other very popular authors for kids books/series.
Graphic novels for younger readers are HOT and growing. I can't really read graphic, but I won't discourage any kid's interest in any book.