They explicitly stated they knew where to read / hear about US politics and did not see the need to have that news domain echoed across every forum.
There are a great many such domains, and the insistence that everything is political is one of the chief problems with modern society. We can, and should, be able to enjoy some things together without bringing up bickering and strife. If you drag politics into a politics free zone you aren't taking responsibility for anything, you are just being a jerk.