Some of the early 1926 dated NID period Ithaca catalogues stated "oil finish" for the NIDs wood. My first year NID Grade 2 28-gauge has oil finished wood. I believe that early on Ithaca decided to cater to the "gun cranks" of the day and do oil finishes. Pretty soon it must have become clear to them that the majority of customers wanted a shinier shellac/varnish finish on their new gun. Some of the Ithaca paper mentions Duco for the stock finish on their Lefever Nitro Special, but most of the Ithaca descriptions just say "finely finished" except for some of the 1926 dated catalogues which say "finely finished in oil".
