Yes, and the man quickly pretended to read the paper even though his mouth is still full of food. I think the comic would've been more effective if there was obvious dog food around the person's mouth, or if the cheeks didn't just look fat.
Possibly it's referencing an affair, and the man secretly had another dog over? Like coming home early from work and finding two empty glasses of wine.
Keep in mind the comic heavily lampoons boomers with a certain zany absurdity. It's best audience is probably Gen X, so I'm not totally sure Millenials et al would dig it.