Oracle database administrator?<g>
You are correct in your research on what MB says. The oil is not really used up, it's the additives in the oil that are used up. Additionally if you are taking short hops, you are not boiling out the moisture in the oil, and acid is also created.
The MB intervals are meant for the vast majority of folks who buy a new car, drive it a few years and trade it. I'm sure that their recommendations will accomplish this. If you fit in this category, follow their recommendations. If, however, you wish to run your car to high mileage, you need to forget that you ever read that information, use quality oil and change oil and filter often.
Change oil hot and change oil often,