Social engineering did not begin with computers, that's just when we put a fancy name on it. Personal information has been used to impersonate people in person or over the phone for a very long time.
I understand, but social engineering 1.5 billion names in a spreadsheet that can be automated is lots easier than social engineering 1.5 billion people in a phone book with no real automation available.
But again, the big difference here is that Facebook gives you the illusion that your data is private. With a phone book, when you opt out, you're opted out.
