Last modified: 2013-02-24 19:28:23 UTC
This is related to bug 34967. Currently the FeaturedFeeds extension will output documentation in <https://www.mediawiki.org/w/api.php> even if no feeds are configured. This is a bit brain-dead. You're telling the user "hey, you can retrieve these feeds... just kidding!" It makes more sense (to me) to just not output any docs to the user if the module isn't actually available. Otherwise, it should be much clearer that the module currently doesn't do anything (and why).
The module is available. We don't want to dynamically disable modules if they have nothing to do - for performance and sanity reasons.