In its $2004$ annual report Heresy Food indicated that Walmart accounted for $22\%$ of its total sales in the year $2003.$ Walmart was responsible for $16\%$ of Proctor and Gamble $($P&G$)2004$ revenues. It is very likely that similar percentages can be found for many of Walmart's leading suppliers. Many of these companies have well staffed offices in Bentonville, Arkansas, where Walmart$$s corporate headquarters is located. There are $$specific investments$$ made by these companies to serve one customer, Walmart. Diversification logic that these firms should vertically integrate into retailing $($forward integration$)$ to reduce the possibility of losses due to Walmart$$s opportunist behavior. Please discuss if it makes sense for firms like Hersey and P&G to vertically integrate into retailing. Use resource and capability logic in your response.