Comment by teraflop

Come on, even if that's true, it's obviously a very different situation.

For one thing, the grocery store is deciding what produce to stock and what suppliers to get it from. They can choose suppliers that have at least a minimum standard of quality. They don't just let anyone on the world slap a barcode on anything at all, claim it's a grapefruit, and put it into their stores.

For another, a large fraction of produce (though not all) is bought in person, and customers can see if it's obviously bad quality before buying it, unlike Amazon where all you have to go by is the product listing for the SKU.