Anything I don't like will be done again mate, so I'm sure they won't be tryna cut corners else it'll backfire and the car will be there for longer than they wish.
It does look like the filler has been put directly on painted surface (it's actually what I thought when I saw the roof and bonnet), but like with all the other areas in the photos, the areas have been rubbed back and then applied. On the bonnet and roof, the low/high spots are no bigger than a 10p piece so they would unavoidably apply a bit of filler to a painted area when spreading it on making it look like it's just been wanged on.