I think most of the time you would want some sort of official response to an attempt to systematically catalog the employees of your nation's clandestine intelligence agencies.
I don't dabble in anything illegal, and I don't scare easily, so they wouldn't really have anything to hold over me. But yeah, I can definitely see that going that route would invite some unwanted attention. It's probably one of the reasons we haven't seen a mass effort to dox the 50k or so NSA employees.