Life's a compromise, Maverick.
So the answer is: For the same reason someone might choose a GTI over a similarly-priced TSI or a GTD over a similarly-priced TDI.
That is, because upon reflection they prefer the better performance and resale value of the higher model to the various options on the lower model (which tend not to retain their value as well).
Not a concept so foreign as to warrant such apparent mystification whenever someone floats it, is it?
So just as some people would forsake performance for creature comforts, others might do it the other way around, even if at first they were only considering the lower model, in which case the reminder of the relative cost of the model above could be timely and helpful indeed.
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