If one wants to buy say a two year old Honda Accord, you will save about $2k-$3k off sticker. Try that with an E320/350.
High end cars drop in value like a rock because parts are expensive, they are complexe, there market is limited, and in general they are pricey to keep.
Works for me, I'm not complaining when I can buy a 5-6 year old S for about $25k. But if one is not a car or MB fan that same $25k will buy a new, almost loaded Camry or Accord.