That is only to weasel out of the legal issues. They are doing marketing stuff that pushes the feature as vastly more capable on the side..For ex Elon Musk tweeting videos that shows cars traveling by itself on unmarked roads..And having declarations such as "The human behind the wheel is only for legal reasons, the car is driving all be itself" and such..
So the actual marketing is based on this unrealistic projection, and only these "statements", which the public will soon forget, is based on its true capability..