But if there aren't labelling laws, then I won't be able to buy real parmesan with confidence.
Price is not a reliable guide to quality. Nor is "shopkeeper's discretion". Knowing that the cheese is made in accordance with strict regulations is a good guide.
> But if there aren't labelling laws,
No one argued against labeling laws except the strawman in your head. The question is whether something is specifically necessary about occuring in the region of Parma in the cheese making process of Parmesan. I don't think it is necessary to not let Kraft call their product "parmesan cheese" for the sake of consumer protection, when existing laws already make it illegal to falsely label your product - for example, trademark laws would not allow you to fake the DOCG label, and existing laws don't let you lie about the origin of the product (Kraft could not say "Made in Parma, Italy" on their product).
> Knowing that the cheese is made in accordance with strict regulations is a good guide.
Again, which is nothing I argued against. You can have strict regulations while not restricting the commonly understood usage of a word. In fact, you seem to agree in your actual usage, since you called it "Kraft parmesan", and not "Kraft parmesan-like cheese product"