Besides, "lost and won" is terribly weird when you just look at money flows but exclude goods. Hey, sell me your $30k car for $1000, you'll be the winner, because you get $1000 from me and we'll not look at the car. Not saying that that's an accurate description of EU-trade, just that it's weird to only look at money flows.
Another problem with that in general is that it's not just about old and new EU members. Luxembourg is an old member, is the tax oasis that works hard to help companies evade taxes in France and Germany, and is also leeching EU subsidies, not contributing to the EU funds.
That's the entire point of the article, the author is not "confusing" them:
>The talks cannot just be about public money, and should not become a brawl between "net contributors" and "net beneficiaries."
I very much believe they are intentionally confusing them because it makes their point. In a "that's basically the same, don't look too hard, just listen to these huge numbers" kind of way.