I agree. I'm not quite sure how it's kosher. I can speculate but do not know. For example, maybe some of this stuff was pre-recorded? Just one possible wild guess.
John Hodgman talked about it in his podcast. He cannot promote any of the TV projects he's worked on because of the strike even though he'd like to, but he is allowed to promote and do stuff for Maximum Fun because it's an artist co-op which is totally separate from the strike/contract.
I don't know the strike rules, but with the WGA possibly still being on strike, and SAG possibly going out on strike, during Comic-Con I'm imagining the panels to consist of non-union background actors who never had speaking roles and aren't in the WGA. Some mild dishing about behind the scenes.