why does Mercedes Benz use alphanumeric car model names?

why do American cars use names like Mustang, Corvette, Camaro, etc? (and what is the term for such names?)

what does this say about the marketing demographics of a brand? Any marketing gurus out there?

if MB was to adopt non-alphanumeric names, what model names would be appropriate for the S, E, C, M and A classes?