Where are you buying your Wisconsin cheese for that much? I’m in the southeast and at Publix I can buy a wedge of Wisconsin Parmesan for half the price of the Italian Parmesan.
The price is about $7, but you'll notice it's only about 1/3 of a pound, so the per-pound price is $20-21. Which, again, tracks with what I've been saying. The only difference is you might be forced to buy a pound of the real stuff when you get a wedge of Parmigiano Reggiano, so there's a bigger upfront cost, but you'll definitely go through the stuff. It's delicious grated, it's delicious on its own, and it freezes well.
