By applying the media system dependency (MSD) theory, this study explores the dependency relations between WeChat use and grassroots-level community group buying (CGB) during a coronavirus disease 2019 (COVID-19) lockdown that occurred in spring 2022 in Shanghai. Due to its technological features, as well as ubiquitous use, WeChat was a reliable digital platform for organising grocery purchasing during a time of crisis when other delivery apps failed to meet residents’ needs. WeChat CGB group chats were created in which lockdown-stricken residents were able to communicate individual needs, interact with each other, and successfully obtain daily necessities. Through 32 interviews with both local and international residents, we identified three dependency relations: understanding (social and self), orientation (action and interaction) and play (social and solitary). Notably, this study uncovers that WeChat dependency in CGB context during the lockdown did not stem from problematic use, but in fact was a goal-solving behaviour during a time of crisis.