I believe all those off topics are created for users to easily gain activity, to increase their ranking quicker. 
Yeah thats true, because everytime i post in our local thread, i've noticed that the threads were deleted that cause my post also get deleted, so now im here in off topic, and i can post whatever i want even though that is not related to the bitcoin forum.. and this really help me to increase my activity faster. Look under your name on the top of the page, you should see "Show new replies to your post". That will take you to a page with all of threads you are "currently in".