Actually it seems that the BMW engineers know exactly what they are doing, follow the computer.
I always find it funny that Americans expect their spark plugs to last forever and their oil to be shot early. Europeans expect to change spark plugs all the time, but the oil should last forever.
Since I have all these free quarts of oil, I may use some of them in my G37. If they change the oil once a year, that should suffice, as we do under 10k per year in each car.