Nowadays, it is common practice for corporations to communicate with consumers through social network sites (SNSs), such as YouTube, which allow consumers to share and comment on companies’ sponsored videos communicating their marketing campaigns. The authors conducted a qualitative assessment of posts written on the official YouTube site of Coca Cola, where the brand asks consumers to join in a brigade against obesity. Results extend the current knowledge about consumers’ negative electronic word of mouth (eWOM), identifying three forms of cynical consumer communication styles in response to corporate campaigns on SNSs: skeptical, passive‐aggressive and warrior eWOM. Managerial implications, limitations and some avenues for future research are indicated.