And if you ask me, they are quite near to reality. If you stand at a cashier of any grocery store like Lidl, Aldi, Rewe, Edeka I do see a lot more card payments then cash. Sometimes at Aldi they have even already activated the PinPad until the customer asks for cash *fg*
And yes, there are a couple if areas where this does not work at all (like small cafes, bakeries) but even there I do see a change, sometimes they have their own bakery-card, for example. But from the overall payments I believe the number of BCG is quite near to reality, that I see.
Also with more and more banks reducing their presence, people tend to use more cards, as the next cash-Machine might be quite a way away