Why I don't link Twitter to Facebook

I don't link my Twitter updates to Facebook for multiple reasons (other than I haven't really researched on how to do it). I know its a common trend and all the cool social media kids are doing it, but I just haven't seen the need for it other than time issues. Another list!

• Twitter is a communication tool. Facebook is an online "home". You wouldn't constantly use your house sound system to talk on the phone, would you?
• The communities are extremely different in terms of interaction. The new newsfeed design aside, Facebook's culture may not align with Twitter's culture.  You probably won't find people retweeting your status update in Facebook, but they'll probably comment on it directly.
• Multiple levels of privacy dictate also dictate how people interact on Facebook. Twitter basically has one -- protected/not protected. Since people on Twitter want more followers, they're more apt to keep things open. Which also makes their Tweets more open to scrutiny.

So basically, the type of communication of application, norms of interaction, and privacy configuration affect the reason why I keep the two networks separate.  Do you link your Twitter to Facebook? And why do you think it's advertised in a one-way relationship like that -- can you link your Facebook status updates to Twitter, or is it just a matter of perpsective.