[IIAOPSW]

I view it as a side effect of linguistic evolution. Sure you could have a bunch of complex rules to strictly type your nouns and limit the type of verbs that validly relate things in one type to another, but if you simply relax the constraint (or just not bother in the first place) metaphors fall out as a natural consequence. See, I just did it. "fall out". Words don't physically fall, but because there's no constraint on using this physical verb to relate non-physical concepts, I can make metaphorical expressions at no additional cost to grammatical complexity.

We do this all the time. We might say a certain fact or circumstance "tells us" something to mean its presence let us make a deduction. Eg "this equation tells us the flow is laminar in this regime". Examples of this sort of thing are abundant.