A couple years ago, I was at a station waiting for a (delayed) ICE train.
I couldn't buy a ticket at the machine or with the app, since the train had already departed (if it had been on schedule).
The ticket machine also wouldn't take VISA / MasterCard, only the more common Girocard (most people still call it EC)
Later, in the train, when I asked the conductor to buy a ticket with my Girocard, he said "That's not a commonly used payment method" and asked for VISA, or cash (not having any to provide change, obviously).
For other readers' benefit: Girocard is not related to Girobank https://en.wikipedia.org/wiki/Girobank or using said Girobank's Girocard to pay bills or collect dole.
Later, in the train, when I asked the conductor to buy a ticket with my Girocard, he said "That's not a commonly used payment method" and asked for VISA, or cash (not having any to provide change, obviously).