I agree with what you're saying, but does this approach scale? What I mean is: (say) Google gets millions of applicants a day. If all of them start calling up Google devs wouldn't that waste a lot of their time? (I guess a reason why this works is that not many people are doing it)

On a related note, I've found that I get a lot of benefit just by calling and speaking to a real person. For instance, an airline representative once saved me nearly $800 on an offer that was not mentioned anywhere else