I frequently point out how Garfield uses pride in his own shortcomings to cope with the world depicted in the strip. Which is not to say he doesn't receive the same punishments or suffer the same miseries as the rest of the characters (or the rest of humanity). He takes comfort in lack of adventure or any basic activity including movement by scoffing at its value, associates negativity with happiness, and boasts about things others would not even speak of, etc. Extending the tendency to its logical conclusion, Garfield often takes masochistic pleasure in misery itself, even when as experienced by himself; this doesn't relieve him from the circumstance of his existence, and other characters deal with the Garfield world in their own ways, but Garfield's defense mechanisms allows him to face it with less agony than Jon and more integrity than Odie.
So lest we think Garfield gets his comeuppance for his gluttony, when the expansion of soft baked goods fracture his skull into a perfect cylinder, think again. Part of the joke is the improbable ability of partially chewed cake to suddenly regain its shape, and several layers to spontaneously stack themselves with such force as to shatter cranial bone from the inside while powerful jaw-muscle pressure is being exerted on it. The other part of the gag, the real biting edge, has to do with Garfield refusing culpability for his gluttony and thievery. No, it is not Garfield's fault that he ate hot cake batter which he stole from the oven: not even bothering to twist logic, but leapfrog it entirely, this is Jon's fault.