If you create original content, you need to write the stuff, format it, and possible work with obtaining artwork and doing art layout. This is more work than just format existing content.
Of course in the end, if it's worth it for you then it's worth paying money for it. I also don't mean to discredit anyone's work, as I'm sure the author did a better job than I did. Personally though, I think such things should be free gifts to the community, but that could just be the anti-establishment side of me speaking. I like the free exchange of ideas.
Now something like Internet Arcana, which involves collecting material from numerous sources (all of which you would have bought too) I can understand better as a for-sale product.
EDIT: And if anyone wants to improve on the formatting, I left the document editable and also provided the MS Word source.