Maybe it's just may way of looking at things, but I think for something to be culturally appropriated, it would need to be done with sincerity.
Ironically dressing up in Native-American headwear for a frat-party doesn't seem like cultural appropriation, just kinda fucked up (like doing blackface).
Not wrong lol. Australian humour is a very tricky thing to understand for outsiders.
I was once accused of being racist for telling a story about how I joked that my black friend didn't need sunscreen.
Unless you understand how Aussie humour works, you won't understand that I'm actually saying "I don't give a shit about what colour your skin is".
For the uninitiated, much of Aussie humour revolves around how much you can "take-the-piss" meaning, "I know where your boundaries are, and I'll show you that I respect you by walking up to that line, but not crossing it".