If no one explains that something is off-topic, how are we supposed to propagate that information, and the culture of what is on-topic to new users of this site?
That's an honest question, by the way. Since there is no barrier to entry to joining this site, there's nothing preventing masses of people arriving and crowding out the good content, which is of interest to far fewer people than politics are.
I'm more than happy to sacrifice otherwise useless karma in order to call stuff out, as the karma points serve no other purpose.
Look at the low quality sub-thread that your comment spawned.