I know exactly what you mean. How about what happened to me recently. Booked in F on a SYD-SIN flight. On check-in I asked what the load was like. Four paying pax in first. Comment from the check-in agent: "It's a great day for staff travel!". Waiting for the door to close there were only 4 of us. Just before push-back the cabin is suddenly full. I don't have a problem with the benefits that airline staff get but loading up the cabin with non-revs is a bit much.