The HTML source attractiveness really matters if the site is about programming, CSS, etc.
On the other hand, layout attractiveness does not matter that much if you're about results... see Google.com
Good advertisers (read: more than AdWords) tend to require traffic verification from at least two of the first three providers you list. Google Analytics is likely for their own purposes.
When you're selling page views and clicks by the thousand or million, you want to make sure you're not being ripped off.
On a quick look I couldn't find that variable referenced anywhere though. And it looks like there are two variables with the same data: js.twitter_widget.bad_words and js.social_stream.badwords
It looks to me like a string resource table for translation, possibly auto-included in multiple page, and used by widgets that exist only on some pages.
