The blog Daring Fireball, which a friend of mine pointed me to, had an interesting comment:

...it’s a fascinating glimpse at just how confused many people are about how web sites and browsers work. They don’t use bookmarks, they don’t type “facebook.com” in the location field. They just Google for whatever they’re looking for and assume the first result is correct.

My friend went further--he argued that many people don't even actively Google, they just type into the location bar of "the internet," read: their browsers, and the browsers do the automatic Googling (which most do when words are entered into the location bar), and these people have no idea whatsoever what is what.