> The goal of such a platform should not be to make money, but to make the market more efficient.
This. Proponents of fully free markets often conveniently ignore that it’s almost always cheaper to sell products of unethical means, absent outside intervention. It’s always cheaper for nestle to sell slavery-produced chocolate than not, and nothing in free market capitalism can effectively address questions of ethics.
Let the government run the comparison platform, and make it mandatory for shops to report their prices daily?
The goal of such a platform should not be to make money, but to make the market more efficient.