When purchasing jobs, the vendor adds a line with a disk, why?

Question

Windows

When invoicing for workplaces with OEM licenses for Windows, FQC-09118 is added to the invoice - 1 pc.
Everytime.
Is it really necessary? The vendor manager says that's the way it should be. Unfortunately, I can't keep track of all changes to Microsoft's licensing policy, so I'm asking the question in a place where there are people who might be able to clarify this point for me.
The question is not about saving money, but about maintaining licensed cleanliness without redundancy.