I spent nine months stationed in Hanau, Germany in 1967/68, we military drivers always stayed in the right lane on the Autobahn except when we would occasionally pass some slower trucks or cars and we used the rear view mirrors a lot.
You had to laugh when Poppa and Mamma with the two kids in the back seat all dressed up for a outing in their Merdedes four door sedan going as fast as poppa could make it go would not move out of the left lane to let some single German driver by himself in a smaller BMW flashing his lights on the Mercedes rear bumper for him to pull over, that was NOT going to happen
For those in this country that don't know, their is no speed limit on the autobahn, you can go as fast as it is safe You did not want to get caught by the Polizi(SP?) passing any vehicle on the right side on the Autobahn, they did not allow any passing on the right side
Different country, different rules