1. High labor cost: Shanghai is one of the most developed cities in China, and the labor cost is relatively high. Service industry is one of the main industries in Shanghai, so the salary level of waiters is also high.

2. Great demand: Shanghai is an international metropolis, with developed service industries such as restaurants and entertainment places and a great demand. In order to retain excellent waiters, employers usually offer relatively high salaries.

3. Fierce competition: Due to the fierce competition in the service industry, in order to attract and retain excellent waiters, employers usually offer higher salaries and welfare benefits. In addition, Shanghai's service industry also attaches great importance to the training and quality improvement of waiters, and many waiters have gained more skills and experience in their work, which has led to higher wages. It should be noted that although the salaries of waiters in Shanghai are relatively high, some waiters' salaries are very low, especially in some small restaurants or cafes. In addition, the salary level of waiters is also affected by factors such as different industries, different regions and different work experiences.