And credit cards in Germany are not "credit" cards as well. At least the one I got from Sparkasse does not let you hold a balance and must be paid in full every month.

Not sure about those, but I got mine around 2-3 years ago from gebührenfrei.de, which is from Advanzia Bank. Seems fine so far…with a minor disclaimer that I don’t really use it much. :-)

I don't have enough experience to speak about CC in Germany, but I don't see why a Rewe or ... boh, Aldi, Mcdonalds, etc should prevent that. I am a bit surprised, to be honest.

Big chains and enterprises, for sure. But there’s still a lot of SMBs not accepting credit cards.

Are these the same SMBs that ... accept only cash? :) Or do they really exclude CCs?

They exclude CCs. They have a card reader but they either have a sign saying, or the vendor will simply say, “keine Kreditkarte”.

If you use contactless payments, this is a non-issue, they can't detect it. Although they wish they could.

So a lot will have in their contract with their processor that they actually can accept Visa/Mastercard, so the sign is there to put you off.

But actually a lot don't, and when you try to pay, even contactless, with a non-Girocard, it won't work.

Visa and Mastercard don't magically let you on their network because you have a card machine.

Because there's a significant a transaction fee if you're paying by credit card, with cash or debit card there's no transaction fee.

The bigger mystery is why stores in some other countries are happy to have a payment method chosen by the customer eat into their profit.

Debitcards, not girocards. I have no girocard since years, and still can easily pay everywhere. But to be fair, the pandemia really pushed this even the small shops.

Ämter only take girocards or cash.

Not true. It probably depends on the location, but last time I paid for a public service, I had no problem using my Visa Debit Card. I think it was not even possible to use cash.