A year or or two ago, I met a writer who had done a book with Book Baby and been happy with them. Obviously I'm a such a DIY-er that I'd never use a service like that, but I thought companies like Book Baby or Lucky Bat Books were potentially useful for people who wanted someone else to take care of things like formatting and uploading books but didn't want to give up ownership or control over their books.
And the other day I met someone who seemed to fit that profile, so I dropped the first person a line and asked, Are you still happy with Book Baby?
Well, you know the whole bit I just mentioned about not giving up control over the books? Book Baby will not allow this person to enroll their books into KDP Select because its exclusivity requirement is not particularly convenient for Book Baby.