She knew she could get fired for showing receipts online and sharing information about customers. You can't do that, it's considered a violation of someone's privacy to show financial details concerning them of any kind without their permission.
The so called "Pastor"'s little note was a smart-ass move on their part but It's not their fault the girl got fired. It's her own fault, no excuses, no scapegoating.
The individual who refuses to defend his rights when called by his Government, deserves to be a slave, and must be punished as an enemy of his country and friend to her foe. - Andrew Jackson