Why recruiter spam works and why you might as well stop complaining

The problem with recruiter spam is, it makes it impossible to tell who is legit and who isn't, and even then, it places the burden of deciding that if I am right for a job on me, and I'm the person with the least amount of information about that. A lot of the time, the company that's hiring doesn't even know what job they're hiring for.

I recently did a phone interview for a company that was looking for an "iOS Guy." Then during the screen, they told me they were actually looking for an embedded C++ developer.

And that's just if everyone is well-meaning but lazy/incompetent. Add to that scam companies like Cybercoders and all of India, which has a 6-month contract for me 3000 miles from my home, and you've got a real mess.

Why do you think it is rational for a hiring firm, to not care about the job description? Wouldn't it be better for them, if only people with the necessary background applied? Then the number of interviews might go down, but the rate of hiring/interview would probably go up, so they would save time and money?

Reads like the author is one of these spammers...