The Daily Cartoonist:

As a general rule, as long as the cartoonist isn’t light-boxing, I try to give them the benefit of the doubt. Even the ones cited above can be excused when looked at individually (the ‘nationalized’ cartoons are easy word gags based on the topic of the day). Collectively, however, the matter gets harder to explain away. Only Jeff knows for sure and the only on-the-record response he’s given me was that “it’s a coincidence.”

All of the examples seem a bit too close for my liking.