Just in case some of you missed Starfleet's post, Book 3 is available on Bookapy. So, you ask "Why should I spend $5.99 when I can just wait and read it for free?"
First, buy the book. Writers deserve something for the great stories they have posted and the entertainment they have provided.
Second, the continuity. No more having to stop an think, ok, where was I and who is that?
Third, be as creative as Carl and come up with your own reason.