The human U+1F4A9, is trying to sell the gun with which he "defended" himself from Trayvon Martin. You remember Trayvon, he was found guilty of Walking While Black in the First Degree and pre-awarded the death penalty by Zimmerman for that.
But even the dodgy characters at GunBroker found this one too scummy for their tastes.
"Our site rules state that we reserve the right to reject listings at our sole discretion, and have done so with the Zimmerman listing... We want no part in the listing on our web site or in any of the publicity it is receiving."
When you are too big a piece of excrement for the likes of GunBroker, you're winning that race to the bottom.