> I don't think I follow your second graph, but you might be suggesting that copyright aside, Calvin is frequently used in stickers on the backs of Chevy and Ford trucks.
Hardly limited to those two (either as locations or subject matter), but, sure, that's one aspect of the use.
> Those stickers are counterfeit.
Irrelevant to the cultural point under discussion, which has to do with what potential future people may be bombarded with in their environment before seeing the source work, not what is legally considered genuine or counterfeit.
> They've been the subject of legal action, and if they aren't today, it's because Watterson doesn't care enough to go after their small-potatoes producers.
Whether Watterson cares is, again, irrelevant, since the issue raised wasn't about the concerns of creators, but how extended copyright protects fans of work from having their children subjected to various forms of unwanted portrayals of the character, etc., of the work before those fans are able to introduce those children to the work in general. Both the specific kinds of unwanted portrayals pointed to as examples ("TV pitchmen for toys and junk food") of the general problem for the general class of works at issue ("great comics, cartoons, movies, music, and books of your childhood") and similar ubiquitous cultural portrayals not effectively controlled by the author (the stickers) for the specific work cited as an example ("Calvin & Hobbes"), so I don't think that there is much evidence that the current effectively-perpetual copyright does much to prevent the general problem being pointed to.
Even if that problem is agreed to be a problem whose prevention warrants government action restricting human freedom (a position I think is itself far from uncontroversial), I think its pretty clear that the existing copyright regime isn't an effective intervention to acheive that end, and so cannot be justified as a solution to that problem.