Btw, the v8 AMGs have similar fuel consumption.
I don't think anyone who buys a V8 sports car seriously cares about fuel consumption. The issue that people have is legacy of the family saloons and sedans which were real gas guzzlers. Large displacement, low power and a hefty gas bill.
I remember our old Chevy Astro van, it took in excess of 20 liters/100km despite only having a V6. Was a fun car (8 soft seats) but expensive to maintain. Fuel cost was high from the beginning and then with mileage growing, reliability problems started. Electric malfunction after another forced the car to be lifted (couldn't even be towed due to 4wd).
A friend of mine had a full size GMC van, we did a midsummer party trip to a festival with it. Ended up paying in excess of 1000 FIM in gas (current adjusted value closer to 900 euros). We split the bill between 7 persons but it still hurt a teenagers wallet lol. But it was worth it. I'll always remember that trip. Pot, booze, loud music, naked women dancing on top of the van with legs shiny from, uh, sweat... and Alphaville (the band) joined us on our bonfire after their concert.
When it was time for me to drive back I hadn't slept for 30 hours. I remember the way back even better than the party. OUCH!