....Just checked my space-saver - Was 35 psi and is now 61 psi.
Hmmmmmm. So now your undying faith in your own stealer must be dashed somwhat, because you claimed earlier in the thread that they do check the space saver! 
I have a copy of the "official" maintenance check list, and they ONLY check the pressures in the four wheels at each corner. The spare is just annotated as "space saver" on the check list.

....I'm confident that they have checked the space-saver's pressure some 25k miles ago but it would appear that either it lost nearly 30 psi (unlikely) or that the guy who did it merely put it to the same 35 psi as all my other tyres. No, I haven't lost faith in my VW dealer as yet.
If he did do that, then the guy is a complete and utter incompetent fcuk-wit, and needs sacking!

It is a very clear, industry-wide standard, that ALL space savers, on all makes of passenger cars are set to an "industry standard" 4.2 bar - which is 61psi. If the idiot can not tell the difference between a normal roadwheel/tyre, and the ultra skinny shiny black space saver, complete with BFO bright yellow stickers, then they really shouldn't even be working on a bicycle, let alone a car. The results of his actions could be very dangerous, and lead to fatalities on the roads.