[stomachmonkey]

Shopify is a platform that has all the front and backend tools in place to allow anyone to set up an ecommerce store.

They help facilitate the presentation / offering of goods as well as the mechanisms to charge and receive payments.

So yes, it's effectively all private sales.

Shopify will require some PII to try and weed out scammers but it's not possible to catch them all so buyer beware.