Weird Machine Learning Job Ad from Google

Below is a Google job ad that I've found today in the Seattle Times, for machine learning positions in their Kirkland office in Washington state. What is weird about this ad is that it was posted in the jobs section in the print copy of a newspaper, and it asks you to snail mail your application to a PO box in San Francisco. My first reaction was - wow, this must be a fake, someone posting a job ad to collect a certain type of resumes, maybe for ID theft, just like many do on Craigslist. Who would read the newspaper job ad section (and I am talking about the print copy, not the Internet version), and then snail mail his resume to a PO box? So I did some search about the PO box in question, and it looks like it is really used by Google.