Small retailers and manufacturers, already crushed by large national brands during the pandemic, are being disproportionately walloped by delays, shortages and other supply chain disruptions ahead of the holidays. In many cases, they’re losing out to giants like Walmart and Amazon, which are spending millions to charter their own ships and planes to move merchandise. Independent shop owners, who have no such recourse, say they’re often the last in line for products because manufacturers prioritize larger, more lucrative contracts.