Final answer:
Co-op advertising is a shared effort between a manufacturer and a retailer to promote products, allowing both parties to maximize the efficiency and reach of their advertising efforts.
Step-by-step explanation:
Co-op advertising occurs when a manufacturer and a retailer share advertising costs. This marketing strategy allows both parties to benefit from the promotional efforts and can help smaller retailers compete with larger ones by providing access to higher quality advertising than they could afford on their own. In other business models, such partnerships may not exist as companies focus on creating and maintaining their own brand identities and marketing strategies. For example, competing with well-established brands like Coca-Cola or Pepsi requires significant investment in creating a brand name and marketing efforts that can compare, which is why smaller entities may struggle without the benefits of co-op advertising.