(I assume you meant "zoning", not "building code". Zoning is what says what kind of building you can make, such as business or residential. Building codes cover things like electrical service and safety, plumbing requirements, what building material you can use, and stuff like that)

Around 92% of US households have a car. Comparing to Europe Italy is around 89%, Germany 85%, France 83$, Spain 79%, and UK 74%.

Unless those countries are also restricting mixed living/business areas they suggest that there is some other more general factor that drives (no pun intended) people to car ownership. US zoning might explain why US car ownership is higher than in Europe but seems unlikely to explain more than maybe 20% of US car ownership.