The market is a concept(概念). If you are growing tomatoes for sale, you are producing for the market. You might sell some to your neighbors and some to the manager of the supermarket. But in either case, you are producing for the market. If people stop buying tomatoes, you will stop producing them. If you take care of a sick person to get money, you are producing for the market. If your father is a worker or a driver or a doctor, he is producing goods or service for the market.

When you spend your income(收入), you are buying things from the market. You may spend money in shops, supermarkets, gas stations and restaurants. Still you are buying from the market. When the boss hires you to drive a truck, he is buying your labor in the market. The market may seem to be something abstract(抽象). However, it is veryconcreteto each person who is making and selling something. It is telling if nobody buys your tomatoes, it won't be long before you get the information. It's telling you that you are using energies and resources in doing something the market doesn't want you to do.