The only legit reason is to protect from spamming, and considering your profile has all kinds of privacy protection, it seems like that would be the way to deal with it. Do you work for facebook? ;)
How can spammers see your profile when it's protected and only viewable by the people you've personally approved to view it? To be honest, though, I didn't even consider your point of view. That COULD be a legit reason, but I'm skeptical...
It depends on your privacy settings -- if you set them to minimal then I'm pretty sure anyone in the world with a facebook account can see your profile.
