Give away writing, get it published?

Can giving away your work actually boost sales of a book?  In this case the author built a following with podcast releases.  I’ve seen his book in stores all over my area, which I assume is a good thing.

I’m not sure if this model would work for everyone, simply because it seems to be a highly individualized and personal way of doing things – building a loyal following, putting in the effort to reach an audience, etc.  What works for one author may not work for another.

At the same time I look at this and pretty much think "fanfic" – because that can get an author a following, feedback, and support and is essentially giving away something for free.  Perhaps the leap from fan-author to published author could be done more easily with an intermittent activity – giving away an original work or works for free in some format, leveraging one’s fans as a starting base.