For food and beverage and CPG sellers running FBA, FBM, and Shopify together, inventory distortion and slow reconciliation are quietly eating margin.
You check three dashboards before you know what is actually in stock. Amazon says one number, Shopify says another, and the warehouse floor tells a different story than both. For food and beverage and CPG sellers scaling across marketplaces, that gap between what the system says and what is true is where margin quietly disappears.
Retailers lost $1.73 trillion last year to inventory distortion, the combined cost of stockouts and overstock, according to research from IHL Group. That is 6.5% of global retail sales. Multichannel sellers feel it first, because every marketplace is its own source of truth until something forces a reconciliation. A case mislabeled for Amazon or a SKU that syncs late to Shopify is not a small error. It is a chargeback, a delisting risk, or a customer who cannot find what they already paid for. Once a business is running FBA, FBM, and a Shopify storefront at the same time, those small errors start compounding across three separate ledgers instead of one.
Fulfilled by Amazon sellers hand off picking and shipping, but they still need accurate landed cost, reserve inventory tracking, and clean reconciliation when Amazon's payout numbers do not match their own books. Fulfilled by Merchant sellers own the warehouse side, which means shipping automation and real-time stock counts matter even more, because there is no Amazon fulfillment center absorbing the timing gaps. Add Shopify DTC or wholesale on top of either model, and a business is running two or three different operational realities through one back office. Most spreadsheet-based systems were never built to hold that much at once, and the workaround is usually a person whose whole job is reconciling exports by hand.
Every marketplace has its own remittance rules, its own timing, and its own way of reporting fees and refunds. A seller registered in a handful of states for Shopify DTC can end up with nexus obligations in dozens more once Amazon's fulfillment network spreads inventory across its warehouses. Reconciling that by hand, channel by channel, at month end is where finance teams lose entire days chasing numbers that should already agree.
Third-party sellers now account for 61% of units sold on Amazon, representing roughly $638 billion in third-party seller sales in 2025, according to Marketplace Pulse. Shopify merchants moved an estimated $378 billion in gross merchandise volume that same year, up 29% year over year, across more than 5.23 million active stores, per Shopify's own reporting. Volume at that scale does not run cleanly through manual exports and nightly batch jobs. It is why more food and beverage and CPG sellers are connecting Amazon Seller Central and Shopify directly into Dynamics 365 instead of stitching systems together after the fact.
If a business is running FBA on a single marketplace, a lighter integration might carry it for a while. Once Shopify DTC, wholesale, and Amazon orders are all landing on the same day, waiting on a scheduled sync starts costing real money. A fifteen-minute delay during a flash sale can mean dozens of oversold units before anyone notices. Dynamics 365 keeps inventory, orders, and tax obligations current across every channel at once, so decisions get made on what is actually true right now, not on what was true this morning.
Western Computer has spent nearly 40 years helping distributors and CPG sellers connect operations to the systems that run them, across more than 1,750 implementations. We have watched the difference between a seller guessing at inventory and one who trusts their numbers, and it usually comes down to whether the ERP is actually wired into the channels doing the selling. If you want to see what real-time sync, tax compliance, and order automation look like in practice for FBA and FBM sellers, watch our on-demand webinar, Amazon & Shopify eCommerce Success with Dynamics 365.