Except everyone is missing the point that you can't find it in a search engine. Has anyone RTFA? That's the entire point of the article. Using a website's local search ability is irrelevant to people that have never heard of the website to visit. The search engine is where people go to find something they don't know where to go for the information they seek. Hell, parental units still go to google first (as in browser default for new window/tab) and type in facebook.com in the search field rather than directly into the browser's location field.
Also, the main page has 2 search boxes if we want to get pedantic about it. Why? I'm assuming as a dev type mindset that they will do the same thing as one is always there while the landing page disappears with use.