In 2006, a video of a middle-aged man verbally assaulting a youth in a public bus thrust user-generated content (UGC) and YouTube into the public imagination in Hong Kong. Using the concept of legitimacy from institutional theory to qualitatively analyze newspaper commentaries about the incident, this study connects journalists’ narratives to the diffusion of UGC by showing how they inadvertently promote cultural support and normative acceptance of this new media category as a consequence of efforts at paradigm-repair and boundary maintenance. Those narratives construe UGC as a legitimate coin-of-exchange: something relevant, familiar, interesting, and appropriate to engage with.