I've noted with concern some blog posts and in-world notices encouraging protests at stores that are distributing stolen content. While obviously well intentioned, I don't believe this kind of action is a valid first step in responding to content theft. Take a moment to read Sioxie Legend's perspective on this, and information about other ways you can help.
Please, if you find stolen content, contact the affected designers first, and give them a chance to file a DMCA. Alerting the content thief first by organising large scale protests at their store gives the thief a chance to move their store or start selling the stolen content under an alt, making it harder for the designers to track them down and take action.
While content theft justifiably creates a feeling of outrage within the community, ultimately it is the designers who are most affected. Please let them decide the appropriate course of action in response to the theft of their work.