You and I watched him talk to someone. Maybe himself. Possibly someone else. The inner layer of his Egg McMuffin? Certain communicable properties of his klondike mustache? The guy was upset. He had already had a bad day, at 9 a.m.
Basically, don't give him a gun. It's a Monday morning. He doesn't go to work today. Nor any day this upcoming week. But do not prolong your gaze. He will tear your eyes out, and shit on them. Because you looked at his.