Sadly, I think this is right. I know several recruiters at a big-name recruiting agency in Silicon Valley, they try to act like an internal recruiter (thorough vetting of candidates, understanding company culture, etc) and they make much less money than if they had just adopted the pay and spray mentality of their peers.

The bright hope for me is darwinian: if enough startups refuse to use these pay and sprayers then they will die off, leaving only the higher quality recruiters. Will that happen? Not any time soon.