I've been collecting comics since 1984 myself. No one ever said that 9.8 was the norm; that isn't the issue. The issue is the staple on the Cap 46. I have seen many, many GA books myself because GA became my focus within 2 or 3 years of when I began collecting, and I have never seen a staple even approaching the staple on the Cap 46 on a book with virtually no other signs of handling wear.
I would challenge you to show me an otherwise-NM GA book in an old-label holder with a staple that looks like that. On the off chance that you could find one, I would suspect pressing first and foremost—but I don't think you'll be able to find one, for the occasional pressing that was happening back then was not nearly as agressive as what's being done now.