Comment by constantcrying

But humans can't really model friction either. Humans use their perception of the interaction to optimize for the desired behavior, for that it is enough to know that more pressure means higher friction. Even subconsciously there is no model of this, it is fine tuned on the fly and in response to external circumstances.

I think the answer to your question is that robots actually need to have complex friction models. If your planning has a need to actually know beforehand how to materials interact, you already lost.