In one of the articles, it stated that the Co Pilot asked for a "non revenue" pilot.
My take, again MY take...
I don't want an 80 hour PPL leaping up front to save the day. I'm an instructor (LCA) and can say it's a lot easier to fly the aircraft (preferebly with automation up and running) by myself than to try and work with someone who has no real grasp on how a modern jet operates. It's not exactly easy with someone who works with different SOP's, etc, but it's manageable.
The term non rev means to me an airline guy is what the FO wanted. Quite possibly however, the announcement was made by a flight attendant anyway.