Another reason for unruled is meme imperialism. I think I am right, and I am out to spread memes.
Both of these reasons are well described by David Friedman in the preface to the second edition of the anarchocapitalist classic, The Machinery of Freedom:
One reason for writing a book like this is to avoid having to explain the same set of ideas a hundred times to a hundred different people. One of the associated rewards is discovering, years later, people who have incorporated my ideas into their own intellectual framework. This second edition is dedicated to one such person... someone who starts out already knowing and understanding everything I had to say on the subjects of this book as of 1973, which makes the ensuing argument very much more interesting.I still hope, in time, to be able to do in this blog what Friedman does in 250 pages in this book.
On the other hand, the blog is also a handy forum for less focused commentary, and I find myself doing that, too. The medium is message? No, but the medium does have at least a bit of influence on how it is used.