Some of those shots to me come across as if the character's glance just happens to be where the camera is. It increases the realism to me.

Even if intentional on the part of the director or actor, there's a bias I think people have to assume something like "all glances at me are because of me". As in, if the events of The Shining were happening, without a camera, surely Torrance would look at the spot the camera happens to be. Or, alternatively, if he never looked in the location of the camera it might be interpretable as avoidance.

I think there's more to it than that (subconsciously drawing you into the diagesis?) but that's how I've interpreted some scenes.