>>723221103
3 never mentions the whole spaceship captain origin of Sam. It feels like it was meant to be retconned out before 4 brings it back.
You could also excuse the T-shirt and jeans as the military loosening standards and just taking any warm body when there's barely anyone left.
I just really get the impression that 3 is meant to be an origin. It works better that way than it just being another day on the job for Sam. He reacts to too many things like they're the first time he's seeing them.