I don't. Many, if not the majority, who visit FR don't leave all forums active; the filter is there for anyone who wishes to use them to limit the subject matter to those they have an interest in. It saves scrolling through headings about angelic pinhead terpsichory and holiday yam recipes. I wish there was a forum dedicated to the Daily fill-in-the-blank-talkshow-host threads, so I could filter those too. That's reason enough.
If you want to speak of wasted bandwidth, how about the zealots who cut-n-paste the same 10,000 word doctrinal screed over and over on threads purportedly dealing with presidential candidates. Now THAT'S a waste of electrons.
A flipping men.