No. Someone is traveling to Europe, going to a restaurant and paying for the Euro nominated beer with his US based VISA and starting to claim that hey, cool, I paid for the beer with USD. You see, I lost a portion of my USD balance and gained a beer.

If you insist that the guy paid his beer with USD, it is going to be very difficult to discuss about anything as the meanings of the concepts are so twisted.

It is quite obvious that using a credit card that then accepts BTCfrom you does not mean that you use BTC to pay for anything but your credit card bill.

It's more like saying you can't buy anything with gold.

Credit and debit cards are just a way of shifting dollars around. Bitcoin is more a commodity than a currency. Yes, you can convert gold or oil to dollars and buy things, but you can't walk into a store and give them some gold flake or a quart of Texas crude in exchange for a candy bar.

> Credit and debit cards are just a way of shifting dollars around

A credit card is shifting a line of credit, an intangible promise to pay, a form of trust, that happens to be denominated in dollars.

We can pretend it's just a balance of dollars, even though it technically isn't, because it makes conversations easier, and in practical fact that's how it appears to work. But that's just a shorthand.

We can use the same shorthand to say someone bought something with bitcoin.

There's no reason to demand perfect technical precision with bitcoin and no similar pedantic precision with lines of credit.

> you can't walk into a store and give them some gold flake or a quart of Texas crude in exchange for a candy bar

I think this is the best test. Here the guy has done that. He walked in with bitcoin and walked out with tacos. When you say that's not really what happened, it feels like a no true scotsman response.

It did not. He gave them dollars, not a quart of crude. That he might have a side deal with somebody else to trade beanie babies for dollars does not make beanie babies a currency.

Bitcoin is not a currency. Plenty of other things are true currencies, so there's no fallacy here.

Was there an individual bitcoin transaction for each purchase? No, he just paid his credit card bill with bitcoin.

Whatever the receipt says is what you paid with; those receipts are definitely in USD.

Sure you could also pay your groceries with lead dispensed from a gun. But that's currently nowhere near broad addoption. It just doesn't meet the definition of "currency", though it will virtually always be current.