Is it simply a matter of personal preference, cultural norms, or social contracts?
So is god (or at least I'm sure you'd agree, the vast majority of gods), so not sure why appealing to a higher power solves this.
If you rely solely on human reason, empathy, and self-interest, you will struggle to establish a consistent moral framework for setting boundaries.
The framework is what's healthy for you and others. Knowing your personal limits and goals. There isn't some supernatural "boundary dimension" you need to tap into or anything.
I did think of the milk example, but I'd argue that's not quite an apt comparison as milk is sort of a generic term for similar things from different sources and often just any white liquid. If we had a different, special word for just cow's milk for example, it'd be weird to call anything else by that name.
I'd argue the equivalent term to "milk" in this case would be syrup. There are many types of syrup, but we specifically use "honey" to mean "syrup made by bees".
Sure, the movies aren't very deep, but the world-building and visuals are pretty great. The emotional beats tend to hit as they should too so it's entertaining fluff. Sure, I enjoy a fancy steak, but I'm also going to fully enjoy cotton candy at the carnival too.
So is god (or at least I'm sure you'd agree, the vast majority of gods), so not sure why appealing to a higher power solves this.
The framework is what's healthy for you and others. Knowing your personal limits and goals. There isn't some supernatural "boundary dimension" you need to tap into or anything.