Why Record Labels Don’t Provide More Digital Booklets on the iTunes Store
The answer is interesting; it’s because they can’t. Apple won’t let them. If a label has uploaded an album to the iTunes Store and wants to add a digital booklet later, the only way they can do this is to delete the original, and create a new album listing with a new SKU. And if they do this, then purchasers will no longer be able to re-download music listed under the old SKU.