It's not that they don't care, it's that they are not knowledgeable enough about the issue and don't have time or will to research it further. That's why we have laws and regulations, so that average Joe doesn't have to research the impact of everything he buys on his body/environment.
With that logic you could say, "why ban dangerous levels of pesticides in the food, if people don't like it, they will not buy the product."
With that logic you could say, "why ban dangerous levels of pesticides in the food, if people don't like it, they will not buy the product."