AFAIK they are printed on demand when the volumes are low. It's incredibly easy to publish (you're essentially uploading a .pdf file). I assume that tons of bo

AFAIK they are printed on demand when the volumes are low. It's incredibly easy to publish (you're essentially uploading a .pdf file). I assume that tons of books only sell a handful of copies. E.g. the only copies of a book that was written by a family member where those that he bought himself.