As mentioned any wine is more of the product of its region than of its processing. This is the whole reason Applellations exist. The better the wine the more expensive it is and thus growers want to protect their brand and governments have agreed. Applellations are legally defined and protected. Growers in Champaign want the premium $ that come from that name just as Napa growers don't want Central Coast growers saying their wine is a Napa wine.

Now an individual may not taste a difference but many people can and this is why certain regions command a premium for their product.