Is it necessary for Japanese duty-free shops to know Japanese?

Hello, actually it depends on the specific situation of duty-free shops. After all, duty-free shops are more aimed at foreigners going to Japan. Maybe Japanese is not very demanding, so it really depends on whether you can grasp it. Under the present circumstances, such opportunities are rare. I suggest learning Japanese before going. After all, Japanese must be used in life and work to achieve the best level of communication.