The only explanation I can think of - and I realize this is crazy - is that there are superstitious people who associate apostrophes with demons, because they denote possession.
That might be the best superstition ever.
Well, demons are just one idiom of possession, particular to a god-haunted world; not that different from alien/government mind control rays, the idiom for a technologically enchanted world.
(cf. the shift from mystical power sources in Golden Age comics and earlier pulp fiction to the scientific/extraterrestrial origin stories of the Silver Age)
