Nothing wrong with laughing at a cartoon. It's that he was sitting by himself in a cafe with his phone on max volume laughing loudly like there was no one else in the room.
But it turns out the tweet was supposed to be a joke and never actually happened (I just learned this when I looked it up.)
mobile.twitter.com/david_j_roth/status/1009431871183351808?lang=en
The way Brit Johnson describes him (and others on 1280) is that he his very immature and easy going. From what I've seen of him, he seems like a friendly guy, but not a guy that take things seriously.