Consumable goods, eg. Toothpaste are things that you may want to be genuine. Sure it may say "Crest", but did it come from the Crest factory, or did a no-name company drop ship fake crest toothpaste to an amazon warehouse, and now their product is co-mingled with genuine crest?
(this is an example, you can google for real stories)
To add, there are stores of extreme coupons who will products (again, lets use toothpaste) from brick and mortar stores on discount, then sell them on amazon. Or buying returns/expired food products from brick and mortar stores, then selling into amazon.
Again, the issue in all this is co-mingling because any genuine sourced products compete with these less reputable ones.
(this is an example, you can google for real stories)
To add, there are stores of extreme coupons who will products (again, lets use toothpaste) from brick and mortar stores on discount, then sell them on amazon. Or buying returns/expired food products from brick and mortar stores, then selling into amazon.
Again, the issue in all this is co-mingling because any genuine sourced products compete with these less reputable ones.