You know, I like how there is this view out there that anyone who's doing classically "business" or "sales" work is not actually working that hard. I know some recruiters. They aren't the world's smartest people, but the successful ones work really damn hard. They don't make more than minimum wage unless they place people.
These guys are cold calling, searching LinkedIn, crawling phone trees, and sending requests all day. When they can they're touching up resumes and doing screening/placement interviews.
Moreover, their technical is different than your technical. It's social hacking and networking. It's learning how to find better opportunities and better people faster.
You might not like that they're Ronin, and work socially. However, they're pulling 12-15 hour days to make their sale.
I would have to add to what you've said, that turnover in recruiting agencies seems to be huge, if my LinkedIn feed is any indicator. They seem to move between jobs as much as many contract developers. And of course, some still will exit the business entirely.
As I don't subscribe to the labor theory of value, I don't care how much effort they put in. I care about the value of the results they produce.
To a lesser extent, I also care if any of the manure that they shovel will stick to my heel.
In theory, you should be able to come out ahead by delegating job search to someone who is better at recruiting than anything else, when you are better at software than job-searching, even if you are still better in absolute terms at recruiting than the recruiter. In practice... well, let's just say that specialization only works if the single best thing you can do offers positive value to the market. If your top skill is wasting other people's time, no one is going to hire you for that.
95% of the author's [limited sample] where recruiters earning a large amount of money for doing very little technically.