I apologize for the morons we have on the property. No bluejet pilot or flight attendant should ever be asking or implying that an offline jump seater should ever help clean the plane. This practice is not "common courtesy."
If I ever see an offline pilot or flight attendant attempting to clean one of our planes, I politely tell them that they are our guests and they do not have to help clean our planes. On one particular occasion, my own inflight crew gave me the evil eye after telling some offline FAs that they didn't have to help clean the plane. I gladly reminded my inflight crew that these people are our guests, and that when we as bluejet pilots and flight attendants jumpseat on their aircraft, we are never asked to help clean. I also reminded them to look in their FAMs because there is guidance for this issue. Cleaning aircraft is part of the bluejet flight attendants' job description......period. Offering to help them is one thing, but please don't ever let anyone ask, imply, or insist that a jump seater should help clean.