What the US needs is a great price comparison service. That is how we get by in Sweden before and after Amazon. Google Shopping is not it.
Such a price comparison service needs a large team manually curating categories and most of all: the product metadatas. So much manual work. Yet it all made sense, even in a country of just 10M people. (The company is called Prisjakt and is now starting to go to shit for unrelated reasons.)