As a matter of fact in the long run pc should become adapted to the habits of these kind of people. Do you think it's their generation only? Nope, i don't think so: a lot of this kind of people in the our generation and in the upcoming generations. I think there right, It,s up to the specialists to get the pc safe without any having to deploy 5 door and 7 locks by the end-user.
Again, one of the advantages of google's strategy: application run at their side.
(btw, I leave my pc on and logged on too)