We worry, quite rightly, about the future of Britain's high streets, in spite of the best efforts of Mary Portas. Tesco may be struggling today, but the effects of a quarter of a century of out-of-town supermarket expansion can be seen everywhere. Charity and betting shops remain the only beacons of light in the boarded-up wastelands. The same is true in France. I guess they blame Carrefour and E.Leclerc instead of Tesco.
On our way to Burgundy we stopped off in Laon, whose cathedral on a hill ought to sue the Michelin Green Guides for its third star. Its Gothic magnificence sits sadly at the end of a dead parade. The inner ville is dying on its pieds. And it is by no means alone. While among the grands crus near Beaune we made a side trip 30 miles south-west to an obscure place called Montceau-les-Mines, a former coal-mining centre whose population has almost halved since the last pit shut 20 years ago.
It was the same depressing picture you find in small English towns. There were a few hairdressers, the odd heavy discounter - in this case rather like Poundland without the style and class - a couple of council offices selling benefits, and rows and rows of derelict frontages. Even Le Sex Shop at number 69 was closed for business.
But one building, on the corner of a windswept car park, shone with new paint and prosperity: a one-star Michelin restaurant, unimaginatively called Le France. It was the reason for our trip, and we were not disappointed. It served some of the best food the gourmand Davies family has ever eaten.
I would travel many kilometres for M Brochot's confit de boeuf, snail soup and hay sorbet. But how he survives in Montceau is baffling. It was like finding Le Gavroche in Mansfield. One can only conclude that the French still have a different set of priorities from us. However bad things get, magnificent food and glorious arms sales to Russia will remain when all else is lost.
For the first time we took our dog with us through the tunnel, equipped with a chip in her ear and a smart blue passport. (It is shocking, though, that there seem to be no standardised EU dogports: the Commission must be sleeping on the job.) It was all very smooth. The French took little interest in our Westie. There was no language test. But on the way back, the complex British rules say you have to go to a vet a day or two before you travel to have your dog checked over and given a worming pill.
What a racket! The surgery was very helpful and efficient, but it took about three minutes and cost 35 euros. French vets must hardly be able to believe their luck. The usually perfidious Anglais have devised a terrific job-creation scheme to sustain every dog doctor in the hexagon during those slack summer months. It is odd that President Hollande doesn't seem more grateful.
After this cultural shock, northern California seemed further from Europe than ever. I went for an immersion course in the new new things. The wealth created by recently floated tech companies such as Facebook, Workplace, Dropbox and Uber (an app to find taxis is now worth more than Alcoa) is awe-inspiring.
Today's Masters of the Universe are not on Wall Street - they live in the Cloud just off Route 128 in Menlo Park and Palo Alto. These nouveaux riches are not like us: they have a lot more money, for starters. And they live exotic lives.
One CEO, proud to present his booming company, apologised for the bottle of water in his mouse-free hand by explaining that he was dehydrated, having completed an Iron Man in Canada over the weekend.
The good Professor Piketty, of course, has these people in his sights. Their squillions are not trickling down to the rest of us rapidly enough for his liking; indeed, he thinks they never will. If Bill Gates is any guide, the next generation of software gurus will in due course set up worthy foundations, though in the meantime they are not exactly enthusiasts for a wealth tax, Piketty's main wheeze. And when in the Californian sunshine, one can easily see why sending large cheques to Washington does not seem to be a brilliant idea.
So it was good to see there was an effective wealth-redistribution scheme under way in our hotel, according to the locals and indeed to a vivid article in Vanity Fair.
Thursday night is cougar night, when predatory females from across the Valley - silicone enhancements to the fore - descend on the drinking holes of the venture capitalists and software geeks in an attempt to encourage them to recycle some of their capital gains in their direction.
The story goes that most of the guys who are now cashing in (or out) have spent the past decade in a garage surrounded by screens and servers, and during that time have not encountered a live member of the opposite sex apart from their mums. So they need to be taken in hand, and there is an agency that specialises in said activity. Trickle-down might not be quite the right phrase to describe what goes down on Thursdays, but I leave any alternative descriptions to your imagination.
On the way home, I was bumped up and sat surrounded by a family who must have bet heavily on the right algorithm. I would need an awful lot of money to want to pay £20,000 for two teenagers to spend 10 hours playing computer games in first class. The cougar nights look like a bargain by comparison.
Howard Davies is the chairman of the Airports Commission. Follow him on Twitter at: @howardjdavies.