You're right, as long as you don't post anything you don't want to be public, you're fine. I have several other issues with it though:
- I don't like that you have to use their interface, and that you have to be a member. For something so pervasive, it should be open (like email is-- you don't have to use any one provider to be able to send and receive messages from anybody)
- I don't like their stronghold on user data, and the issues raised about whether they keep and use my data even after I've deleted my account. That's just freaky.
- I don't like their opt-out philosophy, assuming we want data to be public unless we say so. I also don't like how hard it is to say so.
- It's annoying. Farmville, event invitations, personal messages... they're all a way to publicize things I don't care about. I de-friended someone a while back because she was inviting me to EVERY swing dance in CT. That was fucking annoying.
- I don't have a reason to be on FB. Of my FB friends, I only really have an interest in maintaining contact with about 1/3. Of those, I already have regular in-person contact with at least half. Most of the rest don't use FB regularly (like you). I can only think of two people with whom my primary contact was through FB, and one of them is already looking for other options. Most of my time spent on FB was wasted time or looking up people I haven't heard from or seen in over 10 years (but not attempting contact, since I have no interest in rekindling a friendship with them). That doesn't seem like a good habit to cultivate. Farmville, however...
- Finally, yes, I quit on principle. I don't want FB to BE the internet, like it seems to be for a lot of people. (Ever see that video where people on the street were asked, "Which browser do you use?" and they answered, "Google"? If FB had their way, the answer would soon be "Facebook". If I had my way, it would be an actual browser.) I don't want my FB profile to be the first thing people see when they search the internet for my name. I don't want to fit into the box of "interests" and "looking for" and whatever other BS they ask for in a profile (which I never filled out in the first place).