The problem with that point, as you're citing it, is twofold;
The existence of "rudimentary status markers" is not evidence of a class system. Not sure where you even got that idea; it's not from Hayden.
It's actually unclear from the abstract (and I currently don't have academic access) so I can't check the article, but I'd be curious how Hayden even draws the conclusion that they
are status symbols in the sense that we generally understand, or if he's perhaps defined that term specifically in a way that's more explanatory of his meaning. Because as it stands, any claims as to the purpose would be, essentially, guesswork.