Portuguese here also. Just today at McDonalds, most costumers there were foreigners trying to use the self order machines and, of course, being unable to pay as the machines only accept Multibanco or MBWAY, not Visa or MasterCard.
There wasnt anything anywhere saying that the machines only took Multibanco and the employees there were running around, not having a clue as to what the problem was, just telling everyone that their cards were malfunctioning
I was able to use mbway via NFC just fine and then asked to speak to the shift manager there and explained why it was that foreign costumers weren’t able to use their cards or apple/Google pay mobile wallets to pay. After that the employees were briefed and were able to warn everyone that they couldn’t use the self order machines unless they had a Portuguese (Multibanco) card.
That is to say that Curve could develop an interesting niche by supporting Multibanco/mbway, something Revolut has said it’s working on, not only for Portuguese users but for UK users as 2 million Brits visit Portugal every year. For those people having a card that would work everywhere without any hassle or guessing would be a huge plus and those people would probably continue to use Curve once back in the UK