It is in the 1st Freakonomics book. The post is obviously bait to get traffic. Recruiters are a middleman; they get approached by people offering jobs, and by

It is in the 1st Freakonomics book. The post is obviously bait to get traffic. Recruiters are a middleman; they get approached by people offering jobs, and by people wanting jobs. Some are better than others, just like in every industry. Not everyone looking for a job is visible to all employers, and vice versa - recruiters fill that gap.