You'd be surprised. After all, I'd be almost out of work on my major cases if most people didn't take others at face value; there's a certain amount of implied trust that goes along with any society where there's a decent sense of order and safety. The greater majority of people don't think about the lines where that breaks down. She's been kept too protected from it in the past - she cares about people, and wants to believe in the better part of human nature, and those around her that know that, have ... always been more inclined to make sure she stayed well away from any harsh lessons, to protect her from getting hurt. [Himself included, so far.]

... Which, obviously, is turning out to be very flawed logic.