not everyone reverse parks in a straight line I guess and I would imagine if you were parallel parking on a street it would be handy to
help miss the front corner etc
and how many people in the past have lost a trim/wheel turning into a side street clipping an unseen kerb or a pothole ? or scraped a post or the
garage wall pulling in at home or a multi story car park ?
think of it as a design evolution that's answered the question to more than a few hassle's in older cars by adapting something already fitted - pretty damn clever if you ask me