Multi-Vendor owner/operators need an app or plugin to offer their Vendor/Reseller clients so that they may integrate and sync products and sales from their own website (they may have Magento, Shopify, etc) to MV. It can make life so much easier and error-free. Orders received on MV will flow through to the Vendor/reseller for fulfillment to the customer.
There are apps and plugins already out there which sync to popular marketplaces from popular shopping carts but nothing between MV marketplace and popular shopping carts.
I beleive this will be very valuable for all.