I posted this experience before but it was so amusing I'll do it again.

My late wife and I were travelling in J (Tesco + Amex + 2-4-1 redemption of course!) from YYZ to LHR in 2004 and rightfully joined the CW check-in queue. As ususal this had just a few in the line in comparison to the looong Y one. We were both dressed in full holiday attire, so shorts, tee shirts and I had a weeks worth of stubble.

A smart middle-aged woman joined the queue behind us, eyed us up and down and very frostily said something like, "the economy line is over there" and made a gesture with her hand to the long Y line. "They'll tell you when you get to the desk you know" she then said, after we had just ignored her first comment.

So we get to the CW desks and both become free at the same time, my wife and I went to one and this lady to the adjacent one. Amusingly it turned out it was SHE who was not entitled as she was in Y and had pulled out her husbands Silver card - who was not even travelling with her!. The CW check-in lady politely pointed this out and a short DYKWIA rant started, but the check-in lady stood her ground and pointed the lady over to the Y queue.

As she passed us, my wife couldn't resist smiling and making the same gesture back to this lady, "it's over there you know....and they'll tell you at the desk"