[growse]

> No, there is no obligation. But there’s a thing called courtesy. And as humans there are certain social norms.

In my experience, there are no objective social norms or definition of "courtesy". What's polite in one culture might not be in another. Projecting your own values onto others isn't helpful.

[saagarjha]

Most cultures share some general social norms, such as courtesy to others. I would say it’s actually more unhelpful to dismiss norms entirely just because they have variance.