BMW dealers have the adapter too and have been reported to bess lower priced than the VW one. In over 14 years of driving diesels, I've only encountered the truck nozzles twice. Never low enough on fuel that I couldn't hit the next station down the road.
Yeah, in 2009, facing my first cross-country tow with the TT and the Jeep, I found the VW adapter was $11, and the identical BMW one was $6, so I bought one from the local BMW dealer. Drove all the way from Virginia to Michigan's UP, across US 2 to Redmond, WA, across the Olympic Peninsula, down the Pac Coast Highway to LA, then east along I-40 and back to Virginia and never once needed the thing. It is still in the back of the Jeep "in case."
Just bought a 2012 BMW X5 diesel, and lo and behold, guess what BMW has taken to providing in their diesels? This one is still in plastic wrap, and still in the back where they put it.
So, don't go and buy one, folks. I very much doubt you'll ever need it. Anywhere.