Blame LOROL who for financial reasons decided not to upgrade the ticket machines either at the ticket office nor the machines to LUL standards, so we have the old Southern ticketing system with an Oyster reader stuck on the end of them. (Sydenham, New Cross Gate and West Croydon all have swanky new vending machines)

The former Southern vending machines are not compatible with Student 18+ Oyster cards either, which is why the staff have stuck on photocopied signs above the machines telling customers not to use them.

LOROL's former Silverlink stations are fully compatible with Oyster and sell all products unlike the former Southern stations on the ELL, so there's no excuse bar profit margins.