relies on the supplier being truthful with their documentation for their production

So the supermarket needs documentation and to take precautions, because they are to a certain extent responsible for the legality of the stuff they are selling.

In the real world supermarkets don’t just pick up carrots from some random guy showing up with a trailer full of them. In online markets, this is closer to how it works. Those running and profiting off online platforms should be accountable for what they sell. If Amazon lists electrical products that don’t meet fire safety standards on their website they should be held accountable for selling these products, even if they only act as middle men.

If companies can just take the money without any responsibility we’re fucked.