Is it illegal for store employees to use their QR code to deduct the advance delivery fee?

It belongs to theft and is illegal. If the amount is large, you can call the police.

The employee used the company's QR code to collect money privately. As long as the money collected does not enter the company's financial account, no matter how much money he collects, he can call the police. Strict financial discipline is an important guarantee for the normal operation and continuous development of a unit. This behavior of employees, at a minimum, violates financial discipline and takes advantage of the unit. In a big way, it is to encroach on the collective interests and be suspected of corruption. We must report to the police in time and deal with it according to law.