"Flawless". "Needing new rear shocks at 72,000 miles."
Why?
I've never had a car that needed new shocks, period...
Really. I suppose it all depends on your definition of "need". You could leave the originals on the car forever, the car will still function (all other potential problems aside). Doesn't mean the shocks are doing their job though.
I'd wager that typical stock shocks, which are probably a ~$25 part, are good for about 40k miles before their gradual wear has caused them to be largely ineffective. Something much better like Bilstein B8's will go 100k+, and if you still own the car and they are worn, Bilstein will rebuild or replace them for the life of the car, for the original owner. But that's a far, far better shock than comes out of the parts bin on the VW assembly line, I can assure you.
I replaced the stock Sachs units on my old Z4M at 42k miles, with B8's. It was time. The difference was immediately apparent - the stockers were significantly worn by the time they were replaced.