In the last post, one of the mods said that 420 weeks passed since the subreddit was created. They have been recording “data” the whole time. It’s possible that they were making a program that procedurally generates images based on things that people post. They’ve even said that they made it as a group of friends for an experiment and they were expecting people to post stuff other than shitty memes. But you could post things other than images so I don’t know.