It's not so much whether things ACTUALLY happen without you observing them, it's more that it gives the impression that they do - and that I think is the main thing, and very well done.
You get the sense that world is moving, characters other than the one you associate live their lives, go about their business, animals do their own thing.
It comes across as a living world and yes there is a difference between the life going on around you and events that impinge directly upon you occurring independently of you. It seems to me it would be largely impractical except in specifically-flagged cases for that to be the case because you are the participant in them, so it would pointless if they occurred if you weren't there, unless they were specifically written that way.
Makes sense?