Generic systems do exist:
But integrating something like that into the Sprinter may be a real chore. the standard headlight switch may send data to a controller to turn on the lights, a simple wiring add on may not work. Have you searched any of the Sprinter forums for information?
(I added the feature to my motorhome using junkyard modules from 90's Ford stuff where there were stand alone modules similar to the add on one above. Wasn't easy, but you are right, once you are used to the feature, turning on the lights manually seems dumb.)