Many of the interviewees have created web-based comics, and so there was a longer-than-necessary section on "how do webcomic authors make money." (Like I said, it tried to do too many things.) There was also a fair amount of incomprehension from the older artists: "that's the part I want somebody else to take care of", "how do these kids make money", "I just like it when a bag of money shows up regularly", etc.
Although the comics syndicates do compete with each other, they form an oligopoly. And the gatekeeper function of that oligopoly is, I think, a large part of what kept artists paid. We know people will make comics--- even surprisingly good comics--- for a pittance, and that there are thousands of hopeful cartoonists out there. (One stat was something like 1 in 3500 applications gets accepted by the syndicates.) A gatekeeper can cut off this supply curve, thereby keeping prices (wages) high. You either are the top 1% and earn a decent living, or eventually go do something else with your life.
The web changes this, although in a complicated way because the revenue stream isn't the same. But it means nobody is saying "no" to a comic artist--- they might be a failure in the market, but they aren't getting rejected by an editor. That suggests that the distribution of money will look different, too.