Same sort of thing as this BMW bullshit.
His head unit had the hardware to run rear speakers but it hadn't been enabled by the dealer. To turn it on he had to buy a "special" VW coms cable as the dealer's own cable had "worn out". That cable is only good for a certain number vehicle upgrades.
There's nothing in the cable that degrades but VW have worked out they can use it to charge extra rent for anyone that wants to add speakers to a van they've already purchased.
What I take from that little story is that when my current Golf finally gives out I won't be buying another VW. Once you know that a manufacturer is doing this, you can be pretty sure they'll be no ends to the steps they'll go to rip you off.
Parts that just stop working for no good reason, that sort of thing.
It's inkjet printers all over again.