Someone just posted it one day, and people thought it was funny. It’s like gore posting when you do it at liberals, except it’s a pig with poop all over it’s balls

It's a relic of the before times, much like the site's namesake. A picture of a massive perfectly hexagonal brown bear. Like the other user said it just emerged out of the absurdist bent of the subreddit's culture/humor and grew until it became sort of a calling card.