Just like they are in Southland, oysters are a mania on the Emerald coast of north Brittany and Cancale is the main stronghold for oyster maniacs.
"Non," the man on the seashore said. "Not New Zealand. Breton. Ici!" He stabbed a finger down at the pebbly beach by his galoshes. "Here is the home of the oyster. The capital!"
His dogma came with a strong whiff of low tide and a Franglais soupcon of Hercule Poirot.
Cancale is certainly the place to go for anyone who likes to boast about bivalves and indulge in their obsession with motionless molluscs, and display an uncontrollable urge to spend as much time as possible in the company of an animal with a much better sex life.
The harbour town in the Bay of Mont St Michel, 10km east of St Malo, has 7km of oysterbeds, an oyster co-op which exports to more than 50 countries and a "Musee de l'huitre". Here, for €7 ($11), you can learn all about oysters and their hectic transsexual lifestyles.
The professional oyster farmer who showed me around the museum, having stressed the importance of a highly sanitary and very clean bottom (sea bottom, that is), ended the tour past innumerable glass cases with the punchline: "No wonder oysters don't move much and spend all day in bed. They have no energy left."
You can't move in Cancale for oysters or oyster-philes. Every shop along the front sells them in all different shapes and sizes. Oysters are omnipresent.
From the flat plate de Cancale to the deep Greuse and the sweet Fine de Claire, ladies in Wellington boots cut them open for degustations down by the lighthouse.
All the restaurants (apart from the creperies) stock the soft-bodied delicacies. Huge piles of discarded oyster shells are even used as seabreaks and seawall reinforcements. On Brittany's Emerald Coast you can't avoid getting into arguments of the "My saliva glands are more practised and my palate is better educated than yours" kind.
The man on the seashore watched me as I tipped the oyster into my mouth, letting its retractable foot, colourless blood and delicious three-chambered heart slide down my throat.
I tried not to be too nationalistic about it. Cancale produces thousands upon thousands of tonnes of oysters every year.
He waited for my verdict as I drank another from the sea. "Bon!" I said tactfully. He frowned. "Tres bon," I said. He asked me if they were better than Kiwi oysters. He put me in a tight and awkward ostreicultural spot.
One hand wiped my mouth while the other imitated a wavy, choppy sea. "Peut-etre!" It was pure "Bluff". He slapped me heartily on the back. And then, resuming his Gallic seaside stance, pointed again down at the beach. "C'est le site tres remarquable du gout! Un site extraordinaire!"
I simulated the sea again and thought of Dansfield Park - and we agreed to differ. Although we quickly agreed there is more to Brittany than oysters, as there is more to New Zealand than its oysters.