This reminds me of the occasion some years ago in a Californian restaurant when I was offered a glass of 'Champagne' which turned out to be a local sparkling wine, good but certainly not Champagne. I was feeling distinctly Bolshie so I delivered what I considered to be a polite and masterly mini-dissertation on La France, provenance and proper Champagne, both the region and the wine.
That did not go down at all well with the diners or staff who were adamant that any sparkling or pink wine presented in a Champagne-shaped bottle qualified to be described as such, and that anyway French wine came from American stock. Luckily there were no lawyers present to take up the legal cudgels but an otherwise pleasant lunch was spoiled. Perhaps I should have just shut-up and let it go. On the other hand, why should I have done so in the face of such crass ignorance? I don't think I would do it these days, though. I'm much older and a wee bit wiser., I hope.