Because somebody has to pilot the 18.7-foot Mercedes at car shows.
The Vision Mercedes-Maybach 6 concept was one of the more noteworthy reveals of the 2016 Pebble Beach Concours d'Elegance simply because of the sheer size of the thing. At 18.7 feet long the coupe can afford its gradual lines and domineering presence, but it doesn't look like the most driver-friendly vehicle in the world. Even getting into a parking lot or merging lanes would require skills that only cargo chip captains possess. How the hell are you supposed to see beyond the hood or out the back window?
However, Mercedes had already thought of a solution: Keep the driver out of the car. Instead of getting behind the wheel, the driver just uses a remote control to load the car into its trailer.