While it's important to talk about decency and maturity on FB, I think we're veering off-topic here. The original issue was whether or not to friend someone who seemed like he/she didn't want to be bothered.
Like I said before, I don't have any embarrassing or controversial posts, but I do value my privacy. For that matter, I don't use my real name. I googled my nickname myself and didn't come up with any significant results at all. I absolutely don't want my co-workers pretending to be buddies with me on-line.
I commented on that in my really long post a page ago. I think it's perfectly fine to friend request them. If they don't want to be your friend, they can hit the ignore button. The point of being unsearchable and hidden on facebook was so only people THEY wanted to see their profile could. The way facebook is now, even if you DO find their profile, you can set it so that they see nothing but their profile picture, and mutual friends.
The point of having facebook is to connect with people you know. If you didn't want people you (may or may not) know to friend request you, don't have a facebook. It is so easy to just hit the ignore button on a friend request if you don't want to be friends with them. And if they hit the ignore button on you, big deal, move on with your life. It's fine.