To be fair, it might not be possible for us to know why they did it with much certainty. My initial speculation was that it was a way of clearly avoiding any h

To be fair, it might not be possible for us to know why they did it with much certainty. My initial speculation was that it was a way of clearly avoiding any hint of flirtation or sexual interest (sort of like an extreme form of boundary-setting). This is suggested as a reason in relation to Australian Aboriginal languages the final paragraph of this article: https://www.nytimes.com/2017/01/09/world/what-in-the-world/avoidance-speech-mother-in-law-languages.html https://www.nytimes.com/2017/01/09/world/what-in-the-world/a...