Ah, so many interesting perspectives and characters!
And to answer my own question with that rogue boy of mine:
He's had the Chantry's law hammered into his head since he was a boy, lessons he found boring when he was young, as any boy likely would, and marginally more interesting once he was older. It's hard to pull back from the knee-jerk demons are bad and spirits are good view when it's all you've ever been told, but he does try to take a step back. Sometimes. When he has to think about it, at least.
He doesn't really think anything on the lessons he went through, but he does question just how persuasive a demon can be. People can be incredibly manipulative themselves, they can be persuasive talkers and silver tongued rogues. Sometimes he wonders if spirits and demons aren't exactly the same. Maybe all of those persuasive demons are just as persuasive as the most manipulative of people? And can't 'good' people be manipulative, if it will further the goal they believe is good?
Still, while he might wonder sometimes, when he's bored and thinking back on old lessons while he watches family members shine their Templar armour or cluck about the Chantry, the fact remains he isn't a mage or Templar. He hasn't faced those dangers personally and never will if he has anything to say about it, so his curiosity soon falls to the way side as he shrugs and puts it out of mind.
(Just wait until he gets thrown into the thick of it!

)