Call me Mr. Oblivious but I just recently realized that Mr. Mike Allred was filmed rudely reading his own graphic novel during mass in Kevin Smith's Dogma. There he sat paging through Red Rocket 7 as the camera panned across the congregation.
If you're like me and failed to previously notice this cameo it can be found in the extended church scene which introduces Bethany. Mike is sitting a few pews up from the trio of children slapping at one another.
If you noticed this before...well, good for you.