Which of the following brands are sold directly, according to marketing examples?

The correct answer emphasizes the model of direct sales where brands engage with consumers without intermediaries. Insomnia Cookies exemplifies this because they operate storefronts and delivery services, selling their products directly to customers. This approach enables them to control the customer experience fully and tailor it according to their brand's image and customer preferences.

While Amazon, Walmart, and Apple also sell products directly, they do so in different contexts. Amazon acts as an e-commerce platform that facilitates sales by various brands, and Walmart operates a traditional retail model that involves a mix of third-party products as well as its own. Apple, while it operates its own retail stores, is not solely defined by direct selling since it also distributes products through authorized retailers. Therefore, Insomnia Cookies stands out as a brand primarily characterized by direct sales to the consumer without reliance on broad third-party retail channels.