This is actually not true. As a consumer my choices are constrained by retailers and suppliers (and government due to regulations). They choose based on price what to offer. If all retailers in my area don't want to supply organic food, I can't buy it.
So I have limited power to alter the market. For extremely bad options, there's the choice not to buy, but for necessities, that option is precluded.
Which is why a healthcare "free market" (hint: it's anything but free right now) is a chimera: when you or your family is dying or suffering, you are willing to pay "value based pricing".
The real solution is to delink the "global" supply chain and build up local options. Resilience also increases jobs and tax base, but reduces megacorp profits. Since we actually live in an oligarchy, profits are all that are chased.