Or just because the price OC secured stock at from the supplier is not the price that will end up being paid, as Gibbo pointed out a number of times.
Unsure if they pay up front, or once the cards are delivered, but if the latter then the price might be subject to change due to fluctuation in the value of the pound. At least that makes the most sense, unsure why ocuk should swallow that loss rather than increase the card price.
Again, Gibbo pointed this out numerous times. I don't agree that they should take money for what is effectively a preorder, but give it a rest re: price increases.