Originally Posted by
YYC009
Original post said, in part: "I was behind them with my carry-on and my backpack and some shopping bags."
So if he had a carryon bag (#1) and a backpack (#2) then the shopping bags (#3/#4/etc.) are above the allowable carryon baggage allowance as it is one carryon and one personal article (total of two pieces). The OP admits to having more than two pieces.
Conveniently you choose to forget about the kids : "My daughters walked on the plane in front of me with their carry-ons" And this sentence was in front of the one you present as evidence. Shame on you. Three passengers may have 6 pieces.