I can understand the value of the cars though, the time, the materials, the effort - its all tangible. Admittedly that picture took time, skill and effort, but not even a fraction of what fifty million quids worth of cars would take.
If it was a picture that only that artist could have produced, then maybe yes there is something to it, but to be honest I could fake one that in about an hour, write his name on the bottom of it, and any 'expert' with millions in their pockets would stand there taking in its majesty and talking about what its saying etc.