No, unless this paraphrasing misrepresents the original wording, that's not the issue.
Far more likely is the "Black coffee with milk" suggestion at the end of the article.
If I go to a burger joint that offers an option with no burger patty, and I order "cheese sandwich with a burger patty added", I've gone a bit roundabout but I haven't asked for anything contradictory or 'nonexistent'.
In practice it might seem that a Marinara + Mozzarela might be the same as a Marguerita + Garlic but in practice it may not (for example, amount of sauce, cooking time, etc)
You can of course add milk but then it's a white coffee. As you can add mozzarella but then it's a margherita.
http://www.eatbydate.com/dairy/cheese/brie-feta-mozzarella-s...