From the Wall Street Journal, "Amazon Has Ceded Control of Its Site. The Result: Thousands of Banned, Unsafe or Mislabeled Products."

Amazon has increasingly evolved like a flea market. It exercises limited oversight over items listed by millions of third-party sellers, many of them anonymous, many in China, some offering scant information.
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A Wall Street Journal investigation found 4,152 items for sale on Amazon.com Inc. ’s site that have been declared unsafe by federal agencies, are deceptively labeled or are banned by federal regulators—items that big-box retailers’ policies would bar from their shelves. Among those items, at least 2,000 listings for toys and medications lacked warnings about health risks to children.
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Amazon’s struggle to police its site adds to the mounting evidence that America’s tech giants have lost control of their massive platforms—or decline to control them. This is emerging as among the companies’ biggest challenges.
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Amazon’s common legal defense in safety disputes over third-party sales is that it is not the seller and so can’t be responsible under state statutes that let consumers sue retailers. Amazon also says that, as a provider of an online forum, it is protected by the law—Section 230 of the Communications Decency Act of 1996—that shields internet platforms from liability for what others post there.
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* Last year, the Environmental Protection Agency fined Amazon for letting people sell unregistered pesticides.

* Earlier this year, Washington state’s attorney general and Amazon filed a settlement in state court over state allegations that the company allowed school products on the platform that contained lead and cadmium above federal and state limits.

The article includes a listing of products sold on Amazon that should not be sold, e.g. products falsely listed as FDA approved, products that do not include the appropriate FDA label warnings, prodcuts the FDA says can cause suffocation, products the FDA says contain illegally imported prescription drugs, products falsely claim to be UL certified, etc.

As I've said before, many newer companies, newer tech companies don't feel they need to comply with regulations. The excuse, they're high tech and new, people just don't understand what great things they are are doing for them.

Of course, it all may not matter if the current president continues on the same path. By the time he is done it's possible we won't have any regulations for companies to follow.