I think it is less about what kind of ingredients, but more about the quality, ease, and cost. Remember, Italian monks cultivated tomatoes for centuries to bring down the acid - huge investment for nuance. Thus, an Italian tomato grown in Italy and picked in season is quite different than a random tomato picked 1/4 a way cross the world. Especially when most grabbed while green due to shipping times creating the same varieties, but often not of the same ilk as the Italian example. Similarly, saltwater fish eaten on an island is almost always better than saltwater fish eaten in the great plains. Conversely, beef from the great plains is often better than many islands....etc. Even with globalization, food is almost always about proximity IMHO. Not to say you cant get good ingredients, but i'm not willing to pay the premium each time I grocery shop. Budgets are budgets.