A Slate article confirms my 20-year suspicion that Garfield the witless comic strip is just an adjunct to Garfield the marketing empire, rather than the other way around:
[Garfield: The Movie] is an example of the kind of product that Garfield creator Jim Davis likes to attach his product’s name to: Predictable, unfunny, and eminently forgettable. . . .
The genesis of the strip was “a conscious effort to come up with a good, marketable character,” Davis told Walter Shapiro in a 1982 interview in the Washington Post. . . . Then, he consciously developed a stable of recurring, repetitive jokes for the cat. He hates Mondays. He loves lasagna. He sure is fat.