I don't like that just because I'm a sporadic rather than regular traveller and so can't buy a multi-day travelcard London Underground wants to charge me £3 for the privilege of saving them money on ticketing infrastructure and staff by using an Oyster card. And I'm livid about the lack of logic in this message.
"As your order contains only Pre Pay and/or 7 Day Travelcards you will be charged a card deposit of £3 to encourage you to keep the card. This charge is refundable on surrender of your Oyster card."
So, you want me to keep the card but if I don't you'll give me my money back?