You don’t get too many arguments when a regional name indicates only a geographical source of food or drink, arguing to be able to use that location when your product doesn’t come from there is rather silly. Oh that it was so simple.
In the way of things regional names gain greater meaning over time. They start to signify a certain grade and style of product that is peculiar to that region and then the fact that it is a place name is lost and the symbol represents things less tangible. When the name becomes a valuable trade name with a reputation those who think they have a right to that value get very defensive. What is wrong with that?
Well take it the next step to where the name signifies a category of product that may once have been just a region but now is not. How can you claim exclusive rights to making a certain category of product? We protect with patent a design or process, intellectual property gives some rights to the owner but we are talking about the name of something that many people have the ability and opportunity to produce. The dispute is about the name not the (re)production.
This is related to trademarks that become diluted because the meaning moves from a product that was the name of the eponymous originator to a generic object. So Zamboni was a man’s name that became a generic term for an ice rink groomer. Mr Jacuzzi was a man, now jacuzzi means hot tub. Ditto Hoover, Yale, etc. $$$ Apparently Coca Cola go to a great deal of effort to prevent their brand names from sliding down this path. Should it be agreed that Coke means any cola drink they have just lost their trade name.
So we get to conflicts like the one over the name Prosecco. It is a grape variety and a region and those in Italy who have moved that along now want to own it exclusively. Except that they were not the only ones to work of the use of the variety and developing it into a recognised style … see you in court.
So how do you distinguish between a name that has become common usage, a word that anybody may use, and one that is a trade name that only certain people may use? As usual the people who will make the most out of such a dispute are the professional word choppers.
$$$ I have no idea if these names are now in the public domain or not, I just wanted to use well known ones to illustrate the process.