There are lots of things you don't want to do or that are useless to do over Tor. Useless: logging into Facebook, email, or any service already linked to your real identity. Difficult: most banks/financial services will lock your account if you come from a Tor exit node. Some web sites block Tor exit nodes. Dangerous: Logging into a service that doesn't use SSL exposes you to the possibility of the exit node operator sniffing your traffic and stealing your credentials. There are lots of things you can do over Tor, like general browsing and reading. This makes you safer in the event that your internet connection is being watched, because it's harder to correlate whatever you're doing on the other end. Your SR activity is lost in the noise of all the general browsing. However, as pointed out, there are lots of things you don't want to do over Tor.