They deliver a combination of what producers want to produce, and what people want to buy (measured by what they actually buy), not necessarily what people need or is good for them. Just look at the industrial food complex.
Thought experiment: mechanism does not exist anymore. Would people still want to click nonsensical kettles on their screens and not care about vendor's reputation?
Thus my answer is education, education, education.
I don't believe raw market mechanisms alone are suitable to serve human needs.
Who gets to decide what people "need" or what is "good for them"?
I did not say that someone should assume authority and dictate what people need or want. Just that raw free markets with purely economic/financial incentives fail at the task.
But nutrition science would be good place to find some answers to the 'need' question for food.
The very idea that there is any sort of universal standard for what people "need" or what is "good for them" implies such an entity.
Here's a novel thought: how about treating people as adults with their own intensional stances and allowing them to decide for themselves what they "need" or what is "good for them"?
You're not their parent. "Nutrition science" isn't their parent, either.
Not the fact that we buy with clicks. Not the fact that market does not strongly prefer reputation systems. Capitalism.