I was on a flight recently where 12/14 were j-f opup's! I felt pretty dumb paying for my ticket! It was clear to see on the manifest Which was easy to see in the galley. Although I agree all should be treated equally once in F I think the purser should note who paid for their seat and try and give them small things like 1st selection on shower time. I can't see an opup complaining but I can see a paying customer complaining so sort of makes commercial sense.