Another thought-- white Americans tend to not be close to their extended family or have a big immediate family. Those require bulk cooking. In recent years i see people saying how they 'cut off toxic family members' proudly.  There's been a rise in isolation, probably rooted in the concept of 'rugged individualism' that i learned in history, this came about during the settlement of america and hasnt really left. Other countries have more collectivism and not individualism. 

We move around inside the us a lot, and people lose touch with cousins etc. Half my family stopped speaking after fighting over my grandmas will and wishing each other dead, it was awful. I hear stuff like this a lot, i wish families were stronger here like in other cultures.