I explicitly go balls to the wall to protect my tax documents and cat memes, for a couple of reasons:
I am very passionate about the concept of "You shouldn't have to have anything to hide to deserve the right to privacy."
People should't "poop with the door open" (to use a metaphor), so I keep my door shut.
Opinions and ideals can get people hurt if made public, and I want to protect both mine and those of the people i talk to (even if i don't agree with them).
If everyone took their security and privacy this seriously, nobody would have to worry about some nonce assuming they were committing crimes just because they were protecting their right to privacy. I'm being just one more drop in the bucket.