[harperlee]

They are indeed related, it is not uncommon for banks to offer reduced mortgage rates if you have with them also other products, and often people prefer dealing with just 1 bank. So I would also contend your point of "having just a mortgage with 1 bank and the checking account elsewhere" being the most common case.

And nonetheless you were initially asking why would anyone join a bank that charged them ATM fees; the answer is that it might still make financial sense or be convenient for people. We are discussing about why there is a sizable population for which ATM withdrawal fees makes them prefer paying by card; you can of course "blame the victim" and say that it is the fault of those people not choosing the proper back. But it is just avoiding the topic, which is: this is a problem when travelling to Germany, and it I not a problem when travelling elsewhere in Europe.