The guys are back home, and getting back with their lives. It is sort of a trope that military veterans watch movies with combat and poke holes in some of the silliness we see there. There are always things in movies that don’t make sense to people that live the lives being portrayed; sometimes it is poor attention to detail on the part of the movie makers but sometimes rules are bent to portray things more cinematically.
In this case, the civilian is the one that notices something that doesn’t make sense, and calls it out. What the heck, figured I’d turn the tables a bit. But it really doesn’t make sense, for a world of robots that the Transformers came from, to have facial expressions.
By the way, happy Winter Solstice! The days will start getting longer; light and warmth will follow… eventually.