sadly, this is all-too common in this genre.
these ppl charge as if they were the creators of HoneypotSelect themselves, not just some kids making machinima with someone else's software.
no devs, you are not making game, you are writing stories.
price the m accordingly, maybe go into a bookstore sometime and see how much a completed story is worth.. you might notice that authors 1:do not charge by the 'chapter', and 2 - a COMPLETED novel is about $10-20, tops.
a book set is not the same as a single story though. books have well-rounded endings, regardless of whether they lead into a new story in a new book or not.
think about it, even "the fellowship of the ring" had a well-rounded ending at the end of the book, even though that particular story was not finished in that one book.