Why do car companies do this? Is there a good reason to use an oddball fastener or is this just an attempt to force people to go to a VW dealership every time they need a brake job?
Probably like some instances of Torx, a manufacturer found a new and improved design they could show to be stronger than the previous design. Of course, since a regular hex bolt would have worked, it's a bunch of middle-engineering types having a bratwurst measuring contest at no tangible gain for the vehicle. But hey, at least someone has some improvement implementation fodder for their resumé!
Oh, and some people get wet when they can refer to the complexity of work they had their dealership accomplish on their car, so there's some level of marketing to it.
