When you go to the grocery store to pick up bananas and coffee and you go for the cheapest of each you can pretty much guarantee that you're purchasing something produced by mistreating workers, spraying of carcinogens, destroying rain forests, etc.
Even if you're not producing it you are supporting it. You might go for the the second cheapest banana, and still not know if it's "good" or "bad", but at least the answer goes from "definitely bad" to "possibly okay".
I understand the realities we live with, but blankly accepting the status quo without at least questioning it shouldn't be defended. Why shouldn't companies be held at least morally/ethically responsible in the same way grocery store customers are, even if none are held legally accountable?