(not weird. Yarn is cool, I used to do a lot of crafty things with yarn.)
Perhaps they are aliens, equipped with laser sight meant to distract us so they can take over the world while we're preoccupied... Cause you know cats would look at an invasion and be all like "hellz no. You are not in MY napping spot. See all this earth? This is mine. See all these humans? They are MY slaves. GTFO."