The strip predated the product, although I don't know if there was any licensing agreement back in the mid-1930s. And I've always thought "Dinty Moore" has the ring of a name from an old song or something and McManus used it for his character.
I'm pretty sure the product is Karo syrup, not Kayo. The Moon Mullin kid was certainly named Kayo after the slang term for a knockout in boxing, a KO. (This tells you something about what kind of kid he was). And Moon's fuller nickname was Moonshine Mullins, which was used in the earlier strips and again told you about the character's habits.