Ahahah. I am laughing because everything ended up well.
Yeah, French are cold like that. And that minimum charge amount for cards is quite normal, as they need to pay a fee for every transaction. It doesn't make sense to charge a costumer 2€ if they need to pay 1.5€ for the transaction. Or whatever is the fee they pay.
Here in Portugal the minimum is 5€.
A worse thing happened to me in the UK. I had to pay for a beer, which was 3.5£. The lady said she couldn't charge less than 5£, so I told her "that's OK, I'll drink another one afterwards. You can charge for both."
Then, after I pay, she brings me two 1L beers at once and says "drink quickly because we close in 15 minutes."
Really? She couldn't warn me before!?
LOL! Your story is even funnier - that's just crude! 2 liter of beer in 15 minutes? Even the Brits don't do that! (And they can drink a lot quite fast!)
Oh yes, last winter I was in Lisbon, and I ordered some empenadas, wanted to pay by card, and the guy said NO! Now you have to know, I was visibly having pain that day, walking with a stick even, so he was actually feeling awful that he had to say no, because: the nearest cash machine was quite a steep alley down (you know how Lisbon can be) and I had just walked that alley upwards, only to walk down and up again to pay my 4 euros :')
The empenadas were delicious though :D
They gave me an extra 10 minutes while they were cleaning up. And I managed to drink nearly everything. I never got so drunk so fast. 😅
Ugh - 2 liters of beer - beer belly! LOL! :')