While it's retarded to get mad at old cultures, that have thousand year old traditions, and still borrow from their minority neighbors, because that's how cultures grow/evolve. It's even more retarded to use the term or idea in a country like America, where virtually everything came from somewhere else, just a couple hundred years ago (or much less), and all our food, culture, songs, fashion, traditions are an amalgam of all the others. Those screaming for it to stop, and actually arguing against tolerance and evolution: they're cultural luddites that deserve to be mocked.
If you believe that other cultures should be celebrated and enjoyed, then cultural borrowing and cross-fertilization is a generally positive thing, and is something which is usually done out of admiration, and with no intent to harm. Plus it is completely impractical for demanding they stop. Like anyone is going to stop making Margarita's and Taco's on Cinco De Mayo, because it's a minor holiday? How does that help Mexicans to not allow those festivities? It's gotten to the absurdity that college thought police were attacking people for wearing sombrero's because hats are sacrosanct displays of that culture. (While on the other hand, trans racial people are forgiven, because they are an even bigger minority, and it would be racist to now allow them to switch their identities).
There was a twitter exchange that summed it up. One girl wore a Chinese qipao (Dress) to he prom. She looked great, it was fun, and it paid homage to Chinese culture. So of course some douchenozzle took offense and claimed, "My culture is NOT your goddamn prom dress". Yeah, in a free country, it kind of is. In China, not wearing approved wear was one grounds for being thrown into a re-education camp, but welcome to America.
David Burge (@IowaHawk) had the perfect pithy reply that sums up the hypocrisy of the other side: "Remember: when Americans wear silk dresses it's cultural appropriation, when people in other countries wear Levis it's American cultural imperialism". E.g. the purpose of the creation of "Cultural Appropriation" is to fit the premise that, "America is always wrong! How are they wrong now". If we export movies or clothes, it's abuse of power. If we love other cultures movies or clothes, it's insensitive abuse of power." There is no path, where America can be right -- and that's exactly the point.