What if they are fed up with how many people support the arsonist in their area while personally feeling the arsonist should be publicly executed, avoiding discussion on the fire is their way to avoid getting overly angry with every single person they talk to who keeps insisting on talking about their support for the arsonist.
Or everyone keeps on talking about pro-anti arsonist, and they are one of the few that think dealing with the fire first might be a good idea instead.