Mallory hates Bob. Bob has a blog about ponies, and Mallory knows that a large-ish fraction of Bob's traffic comes from the ponies Subreddit. If Bob's stories stopped appearing there it would make him sad, and Mallory, the venomous little sadist that he is, would rejoice. Here's how Mallory could accomplish the deed:

• Watch Bob's blog closely to make sure he's the first to submit Bob's posts to Reddit.
• Include some words that will trigger the spam-filter in the submission title. Any combination of "viagra" and "cialis" will do just fine.
• Sit back and cackle evilly.

Now Bob's post is sitting in the spam queue on the ponies Subreddit. Since the post has already been submitted, the nice users who usually submit Bob's story can't re-submit it to the same Subreddit. Maybe someone will notice and alert a moderator, but by the time they un-ban the story nobody cares because it's already 10 hours old and on page 50 of the /new queue. Bob thinks nobody loves him, and retires to live out the remainder of his years, sad and lonely, in a small, unheated hut on a hill outside of town.

In this story, I am Bob, Mallory is some innocent schmuck who submitted my last post to the programming Subreddit while they were silently banned (how were they to know, right?), and the small, unheated hut is the Aeron chair in front of my desk. The blog about ponies, however, is entirely fictional.