Culture is a fundamental facet of identity. We all have culture(s) we identify with. But what counts as cultural appropriation is nuanced. Most of the time — but not all — adopting food is not appropriation. Most of the time — but not all — adopting ritual is. Whether or not adopting practices around clothing, hair, body decoration, home and environmental decorations are appropriation is impossible to predict in the abstract.
One nuance is that appropriation depends on who you are and your relationship to the locally dominant culture. In particular, adopting common practices of the dominant culture is often not considered appropriation — in fact, it may be considered a measure of that culture’s dominance. For example, most Christians in the United States don’t object to secular choirs singing Christmas hymns. Translate this same example to a non-dominant culture’s religious holidays, and the situation becomes much more ambiguous.
What makes the difference? A problematic explanation might be that because a locally dominant culture is aligned with the dominant power structures, that culture is less deserving of respect. In this perspective, the culture of, e.g., white Christian Americans in inherently less valuable than that of other cultures. This perspective is problematic and wrong.
In my perspective, a better model is to think of cultural practices as being subject to a social immune system. A dominant culture has the ability to defend itself. If a cultural marker is used inappropriately, there are plenty of members of around to object, and they generally will have ways to be heard. The social immune system is well tuned toward violations of the norms of a dominant culture. This leads to a situation where people can generally assume that what they see is what they get with regards to adopting the cultural practices of a locally dominant culture.
On the other hand, when markers of a non-dominant culture are used, there may not be people with the right background to say whether or not it is appropriate. Or they may object but not have the power or safety to make themselves heard. Thus, when we see a practice being adopted from a locally non-dominant culture, we can’t just assume that it’s okay. It might be problematic. It might be fine. When faced with this uncertainty, we should tread with caution. The social immune system isn’t tuned for these situations.
This isn’t an argument for static, isolated cultures. Cultures evolve over time, and practices can join or leave the locally dominant culture over time. Fashion and food, in particular, are areas of frequent cultural blending. Just as a physical immune system can learn to recognize new things as acceptable or unacceptable, the social immune system can move from “don’t know” to providing reliable feedback that a practice is or not okay to adopt.
One way this evolution happens is through invitation. Cultures are not monoliths and no single person (or group) can authoritatively speak for a culture. Still, as a rule of thumb, if a member of a culture invites you to participate in their practices or gives permission to your usage of a practice, then it’s probably not appropriation. So don’t avoid learning about and participating in practices that may not be a part of your culture. Don’t give into the fear that you might mess up. Instead, keep listening, keep asking, and let the invitations of others help you navigate the way.
(A lot more could be said about this. Invitation is a nuanced topic. For example, an invitation to participate in a particular event can be taken as permission to participate at that time but not necessarily as permission to duplicate the practice on your own. However, a more general invitation, such as selling a cookbook, is a pretty good indicator that you can duplicate the practice on your own.)