Why don't individual industrial and commercial households, restaurants, hair salons and other shops on the street have labor contracts and social security five insurances?

Employees in hair salons and restaurants may belong to employees and are adjusted by the general principles of civil law, so they do not need to buy social security; Employees of companies and other employers are laborers, and they need to buy social security because of the adjustment of labor contract law.

Further reading: How to buy insurance, which is good, and teach you how to avoid these "pits" of insurance.