Apparently, I was wrong. The publishing side of Marvel Comics, for example, turns out to have a remarkably high 38% operating profit margin.
Marvel’s publishing division finished 2008 with sales of $125.4 million, virtually flat with 2007 when revenue was $125.7 million. Operating profit slipped to $47.3 million from $53.5 million, which the company said was primarily due to ongoing investments in digital initiatives.
As these numbers show, comic book sales have proven themselves to be virtually recession proof (which makes sense given that comics books first took off as a media form in the Great Depression). Even in the economically catastrophic fourth quarter of 2008, Marvel's sales were actually up.
In contrast, big time publishing company McGraw-Hill has a roughly 15% margin, earning about $1.0 billion of net income on $6.8 billion of sales in 2007. The comparison isn't precisely apples to apples, but comic books appear to be quite a bit more lucrative than traditional books.
I wonder if the profitability of comic book companies has anything to do with the relative disorganization of comic book writers compared to, for example, screen writers and playwrights, who are almost universally members of unions. So far as I know, there isn't a mangaka's union in the United States, and comic book writers don't command the huge royalties that their Japanese counterparts and best selling American authors in traditional formats do. The dominance of a smaller number of comic publishers in the industry, with Marvel and D.C. Comics overwhelming all other publishers in the comic book industry, could also be a factor. The fairly thin distribution network, since there are far fewer comic book stores than there are book stores, could also be relevant.