Dear Nicolas,
thank You for your answer!
It is unfair business practice to find out that a ticket is doubled before you buy. At the railway companies I know (DB, ÖBB, MÁV, ZSSK), one see the website/app the normal second-class ticket price, not e.g. the Bahncard price.
Thank you, it’s not so nice Sunday because there will be an empty my pocket on Monday. 😞
All best,
Máté