Unless a Zeenut has the coupon intact, (excluding 1911-12), in my opinion, it should not receive a numerical grade. If the coupon has been removed, it pretty much reduces the card to "Aut".
I don't have a lot of Zeenuts because they are hard to find, but collect 1916 and 1917, and will pick up any I can for the right price from other years also. I won't pay more for a holder, but it would not stop me from buying the card.
Here's a 1917 Zeenut Roy Corhan (2 seasons in MLB, STL, Chisox). I think I was the only bidder at a start of $50 in a major auction. I thought I paid a little too much, but I liked the card. Although it is graded "poor", I'd say it's above average compared to other Zeenuts in my collection.
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