In reply to Smiffy:
I agree, there's one reasonable shop in Bourg d'Osian. The Au Vieux Campeur in Grenoble is very good, but isn't quite in the city centre and if you get the one-way navigation wrong it can be a bit of a trial to find by car. But otherwise definitely worth a look if passing.
> It is just something to use up time on rest days / poor weather.
If having a rest day, supermarket run or escaping the mountain weather, this place is a bit of a laugh for an hour or two:
Le Vernis
The lower crag is quite shaded too.