You refer a friend or family member to a book because your happy with the way the book has handled your business, much like you would refer a friend of family member to a dentist or auto insurance agent.
Referals from books are a thing of the past, and I think a lot of the incentives offered this year will diminish at the end of football - at least by the better quality books.
Books on the fringes will still offer great incentives, but don't expect bailouts.
JC