He means actually working with them, not the spam. They seem puzzlingly worthless. I actually asked a guy at an interview, years ago, "Why do you use recruiters?" and he said it saved time going through resumes. As if that's worth a fat commission: Using some lib-art knucklehead who can distinguish 5 years of .NET from 3 years of .NET.
Also, they sometimes call your office. If you don't have a good relationship with your receptionist, never ever use them.