Why didn't the wholesale market in the market go? Where did these go?

Nowadays, wholesale markets are generally planned on the edge of cities or near logistics parks. 1. Reduce transportation costs, 2. Reduce management costs, traffic management costs in the process of vehicle transportation, and management costs of personnel flow, 3. The scale of development, generally there are few people near the edge of the city and the logistics park. Moving these highly mobile markets in the past can drive the flow of people in these places to rise, upgrade the surrounding industries such as small shops and restaurants, and then build houses to support and promote urban development.