It is a valid question. There are many who come into pen turning and making from various backgrounds and with experience with different finishes that work well in particular situations.
Where wood pens are peculiar is how they are used and handled differently from other wood implements and furniture. They are held by sweaty hands, used a dozen times or more a day, subjected to cold and heat such as in a car, humidity and dry, inside and out, very warm moisture from a shirt pocket, crammed into a purse with keys, compacts, cell phones, loose change and more. And this is DAILY.
You won't find musical instruments or fine furniture that goes through this kind of use, or a finish that is made for such a wide variety of situations. Gym flooring is about the closest thing to pen abuse and use. Shellac won't stand up under normal pen use. There are people who really take care of their pens and they go to lengths to keep it clean and protect it. A person like this would probably be able to use a Shellac finished pen without a problem.
