Well, if the dudes are legit that money is nothing, it takes a long time and trial and error, and yes sometimes a lot of money (dates, divorces, clubs costs, books you bought,bootcamps, products, memberships, pregnancies in some cases, abortions etc...) and more to find out what works and what does not, then you have to put a book together that takes a lot of time, you have to pay editors, websites etc...
the main market is guys that are coming out of break ups or divorces, and guys that are rejected or friendzone... Usually most books have money back anyways...