What caught my eye is that I'd certainly seen books with that title before. They are usually prominently featured at the local mega bookstore. A quick check of a major brick-and-click reveals that the new Oliver James book is (at least) the third book to sport that title and there are scads of books and articles and talkshow homilies devoted to the subject.
The point of this epidemic of print on the subject?
To. Sell. Books.
There are a mind-numbing number of books being sold on how to save money and publishers are making a mint on the subject. You can't walk into a bookstore without running headlong into some schmantzy display of tantalizingly marketed books that are designed to get you to buy a book - that you probably don't need - the premise of which is that you buy stuff you don't need!