The fake stickers that don't have a manufacturer are dodgier than Accy's mackerel and blackberry crumble. The Bafang one is more convincing. Train staff are neither trained nor paid to make an ID, so a blanket ban is then only practical method, as unsatisfactory as it may be.
As usual the law abiding suffer because a minority taken the p**s and the authorities are slow to act.
As an aside, those fake stickers are pointless. Possession of a false instrument with intent to deceive stands a good chance of a suspended sentencemif youre lucky. What kind of prat risks sharing a bedroom with bubba just to avoid a potential 6 points on a drivers licence they probably dont even have? Its like packing a machine gun because you dont want to get caught with a penknife.