A number of years ago I was jumpseating on Northwest. The cockpit was really quiet, so I didn't say anything. A couple of hours into the flight the F/O had to get up to use the restroom. He packed up all his charts, put them in his flight bag, put on his tie and hat and uniform jacket and overcoat, and took his suitcase and flight bag with him to the restroom. While he was gone the Capt and S/O told me that he had scabbed on their last strike.

Joe