"We'll empower you to easily sell your stuff" that leaves power and agency in the hands of individual companies. WordPress + WooCommerce, PrestaShop and Magento already do that. Drop $10 to $20/month on hosting on DigitalOcean, install Wordpress, install WooCommerce, buy a cheap theme, buy whatever extra plugins you need, setup your payment system (PayPal and Stripe are supported), and you're off to the races. And it…
But she hated the web-based admin interface and it was way too cumbersome to get anything customized, products added, etc. In the end it just wasn't worth it and she's now on Weebly. Shopify and Weebly have their own faults and can definitely be a pain if you want to do anything off the beaten path, but for the non-technical user who just wants to sell things I see the value over a self-hosted Wordpress install.