Some time ago my "25% DB Card" ran out and was not active anymore, but the app did not display a warning. Even when buying a ticket from the app, it still had the "25% off" option activated by default.

Result: huge fine (something like 200 euros) on the train + I had to buy a completely new ticket (another 100+ euros) because the ticket I had bought ( which was 75% of original price) was considered completely invalid. I tried in all possible ways to get this fine reduced, as it was an honest mistake and arguably caused by their UX, but they did not budge.

I hate hate hate Deutsche Bahn with a passion, yet I still use it cause I'm an idiot who doesn't want to fly for short routes.

https://en.wikipedia.org/wiki/Pfeilstorch

I think that was just a way to ethically cheat the fast...In southern Germany they got around it by wrapping the meat in a dumpling (Maultaschen), so that god wouldn't notice: "The Swabian German nickname for the dish, Herrgottsbescheißerle, means "small God-cheaters""

https://en.wikipedia.org/wiki/Maultasche#History

EDIT: just remembered another similar cheat, where beavers were defined as fish, allowed to be eaten at lent.

Kinda like the discrimination DB does for people using paper tickets vs those using the DB Navigator app.

I don't understand why this is not the default to be honest, and why people are not advocating for that