This is a very narrow view. I am Italian-American in the literal sense (a citizen of both countries), we are fairly recent immigrants although I grew up in the US. There is simply no way for the average American to be that exact regarding Italian cuisine without having grown up there. The same way it is nearly impossible for the average Italian to be that exact regarding American cuisine without having grown up here. Asking someone to understand the different names and types of biscotti or cantucci, for instance, is similar to me expecting you to know the various local varieties of lobster rolls depending on where in New England you are, and then also holding you accountable to know that someone in New Jersey will probably not be able to make you one, and someone in coastal Virginia may not even know what one is.

Everyone does the best with the words they know. Help a tourist out, they'd do the same for you in their home.