✔ 最佳答案
1. To provide a place for customers to choose things to buy. Factories do not have professional people to sell the goods.
2. For convenience of customers. Because they go to a certain place for shopping like supermarket for domestic goods and Mong Kok for clothes, shoes and electronic appliances.
3. To reate competing, since there are so many different kinds of goods in the market, sellers has to improve their service and products to get more business. So it can help to improve the quality of products and reduce their cost.