Ask HN: Why Recruiters still believe in cold emails

I'm a SWE in the bay area with 8-10y of exp. I get about 1 to 3 cold emails a week from recruiters about positions. I'm talking about basic emails. Here is the most recent one:

"I work at a tech startup called XYZ we’re a NN person team and we recently launched into the SF Bay area. We work with some of the best SF tech companies from early stage to IPO, such as AA, BB, CC, DD, and EE. Our mission is to discover the best talent bla bla bla blabla... Would you have a few minutes to chat sometime today or tomorrow?"

First of all, how do recruiters get my private email address? I don't share it, only with a few close people or my current employer (as well as the ex-employers I guess). Second of all, why in 2016 recruiters don't make any effort in trying to get attention from people who already have high profiles, great jobs and no reason to look for a change? Just curious... there's absolutely zero innovation in that space.