The Rewe deal sounds really good, I haven’t been able to grab one of those yet. It’s probably because I’m not in Germany all the time. One thing to note is that karma points are awarded for a minimum of five euros spend. For the bahn.comfort status you have to spend €2000 within one year. My Bahncard is in the form of a credit card, which is renewed each year. Having the credit card protects the points from expiry.