Most of the time, yeah. The margins are massive. Most developers are terrible negotiators who roll over for $40-75/hour (and think they are getting a great deal), when recruiters and consulting firms routinely charge their clients $150+/hr on the back end. It's pretty easy to see why the word "loser" is used in the article to describe these people.

You can use this to your advantage in permanent roles where the recruiter's cut is a percentage of your starting salary.

That's right, one of the first steps to becoming a ruthless sociopath is to align your interests with the right people. IT could learn a few things from the pro sports/entertainment worlds. A good engineer ("rockstar", as it were) can easily make their corporate overlords just as much money as a real rock star or pro athlete.