I don't really do anything particularly for VW drivers. But I try to be considerate, letting people out and stuff and the 1 car rule is good but it annoys me when you let one car through and the car behind pushes it's way through as well.
When it comes to VW's I do tend to vary according to the car. I recon 60% - 70% of Mk4 and Mk5 Golf drivers aren't really dub enthusiasts and even higher for Passats as they are often company cars.
But when it comes to Mk1/Mk2/Mk3 they are much more likely to be dub enthusiasts, and the older the car the more likely it is. So I tend to be more helpful towards them. The same for old Beetles and campers.
I spose, I was raised on Dubs, (we had a Mk1 Golf, a Derby, a Mk1 Jetta and a Santana) so I guess I link dubs with good family values, but then that goes out the window when some idiot has driven his Golf through a branch of Maplins, Halfords and a plastic bin factory with is eyes closed.