>>80018483/v/ constantly has off-topic threads with users priding themselves in them being better than the actual topic.
Other than that, besides /tv/ or maybe /sp/, I can't really be talking, since I don't browse many boards, myself. Most other boards stay on-topic, with the most I've personally seen of any rift being on /m/ where some complain about what is considered on-topic or not, like toku stuff, or /tg/ where no one wants quests stuff.
I don't really think it's so much about being "off-topic", but rather, people enjoying and desiring certain exceptions, like Toonami, Digimon, Godzilla, or, as the case right now being, Dragonball Z Abridged, and the spontaniety of something and seeing how a board may spin it to reflect itself is also something that plays a part in how much people care about it.
I don't know.
