Read this strip at gocomics.com.
Another Snoopy power! This makes sense once you realize that Snoopy's open mouth is magnetically attracted to treats. (Oh if you want to be boring you could say he just smelled it.)
Snoopy is slowly becoming looser in design, and it has been good for the character. He was almost like a piece of clip-art at first, but now he's slowly growing larger (more obvious when he's walking -- note how large he is in the last panel compared to the rest of the strip) and his mouth is capable of opening wider, in the second panel here particularly. He's slowly turning into the outgoing, wildly imaginative werewolf we all know.