You do realize this applies to all currencies? YEN, CNY, CAD
Dell USA, AFAIK, accepts only dollars. Dell Brazil accepts only reals. If you want to pay them with some other currency, you must find a way to convert them to USD or BRL, respectively, and send those to the companies.
I have used my Brazilian credit card, whose bills I pay with BRL, to pay for hotels and other stuff in the US, Europe, Japan, etc; but it was always the credict card company that exchanged my BRL for USD, EUR, JPY and deposited these to the merchants' bank accounts. Those merchants definitely did not "accept BRL", anymore than Dell "accepts bitcoin".
This discussion began with a certain someone making false statement that BTC is not accepted as payment for "normal" every day items.
My point was that it was incorrect assumption because payment processors do help merchants take payment from other currencies including BTC.
The example argued that was used did not acknowledge that even if product is priced in USD does not mean that you can't pay for it with other currencies, like CAD, BRL, CNY, YEN, BTC as long as they payment processor used by the merchant takes said payment.