If I understand you correctly, then it does seem true to me that nature has no agency. However, when the choice a consumer has is to either pay the asking price for a <em>needed</em> drug or to die then I think the consumer has no meaningful choice at all. Given how unequal the bargaining power is between the buyer and seller in this situation, it's hard to see a free market solutions applies: it might be efficient, but it's also brutaly inhumane.
I know I've set up kind of a straw-man. It might be that the consumer could choose to forgo an expensive drug or medical procedure without fatal consequences, but that's not the interesting case.