You think there's a high number of Spanish tourists going over the border, to Lisbon, only to ask for a pomegranate juice? And you think they are just going to assume that their language, culture and coloquialisms are the same? That's a lot of assumptions being made.
Was the waiter Portuguese, or just an immigrant that had a scary experience with a foreign Tourist?
And again, did anyone here even looked up the word in O.G. Portuguese? Because the author of the article surely didn't (otherwise I'd find it in the article), and all the people in the comments seem to be making a lot of assumptions about cultures in Europe.
It is bad, but I'm not going to make rash assumptions because I don't have the full context. If the waiter is incompetent, that's one thing; plenty of incompetent, jumping to conclusion people around. The waiter could be that.