I think that is because people tend to try to find the inflammatory, argumentative, confrontational topics because they are bored and are looking for a good scrap instead trying to have and informed, friendly, informational discussion. It does tend to get annoying that it seems to take, on average, about 7-10 posts for a topic to get completely off course (see rail-roaded) by GW haters who think that it is just plain tomfoolery to enjoy playing 40k, which is funny. I personally don't have that kind of time/energy to convince people that their game of choice can no way be fun. Just plain crazy, but alas, to each their own I guess.