Actually, it is exactly like your car since automotive manufacturers make very few of the component with most being manufactured by companies like Valeo and so on with the option to either procure the original OEM supplier part or third party alternative when you want to replace something. Beneteau lets you procure some of the OEM sheets such as the jib sheets they just don't let you procure all the different running rigging used.
I'm aware of all the US rope manufacturers, I was just curious if anybody knows the supplier that Beneteau uses for their sheets (I assume they are French) since I like the color and quality of the sheets and other running rigging shipped with the boat. It's reasonably to ask the question as all of us have different preferences.