>>77017487I don't know if the new digital versions come with the original letters pages, but there were the occasional complaints from religiously-inclined readers in both the original Ghost Rider comic and the Son of Satan series (more so the latter than the former, though).
The best explanation I can come up with for stuff like Ghost Rider and Son of Satan getting CCA approval is that the writers and editors followed the letter of the Code—so long as they didn't feature the banned elements specifically mentioned in the Code, they had a case for publication. It also helped that by the mid-1970s, the CCA had drastically relaxed its formerly draconian standards (You should check out some of the stories DC managed to get away with in its war and horror comics anthologies from the late 1970s and early 1980s).