The instant the Freepers see anything that doesn't conform to their worldview, they immediately delete it from their website, lest they have to face the evidence of how wrong-headed and hard-hearted they are.
They call such deletions "ZOTS" and have come up with quite a few graphics to request that such a zot happen whenever 'unmutual' articles appear on their tightly controlled echo chamber.
Then they cheer and celebrate that they have once again avoided a confrontation with an opposing point-of-view -- and once again kept other delicate Freepers (who can't handle facts) from seeing one.
"In Before The Zot" is another way of saying "book burning."