You can safely return that oyster card and get your deposit back now :D

I live in London and recently passed a convenience store whose signage advertised the usual stuff: "Fresh veg. Off licence. European specialty foods. Oyster". I was genuinely confused for a second that such a place would carry such short shelf life seafood...

Pre-pay card are gone here. The only people I know now who have an Oyster branded card are those who get discount or free travel.