Your guess is right, I'm living in Germany. But I think I'm in the minority here - I really don't know any German who is in their twenties without a driver's license. I'm not German though and I used to have a license back in Istanbul, which is not valid in Germany. I didn't bother getting a license here because you can get a Bahncard from Deutsche Bahn, which covers 90% of one's public transportation needs. Maybe it's a similar story in other European countries but I think most people still get a license just in case.