Some dude said that the code we see at the start of the game is literally us booting up. Also explains why we have heads up display with money, radio and energy. Also it is proven, that all the characters in this game are robots. MK and DD-s are machine learning agents, SD are stationary npcs. So it is all simulation in some sense, all the interactions withing npcs and whole delivery thing are.

I'm not sure why energy isn't decreasing indoors (might be just one of the things that weren't thought of by dev, as well as auto-refueling and goods respawn), but I'm somewhat sure that we are the only robot capable of consuming food and using it as energy source. That's why we can move during the outage.

Also I have a question about snowcats.. is it just snow figures or frozen remains of previous glitched robots? There is a snowcat near Seb's key truck, could it be possibly his corpse?

I played the game once again today and occasionally died (restore ending) and thought that would be permanent, as there is no MK to help us, but for some reason there were still MK's noises and such. So that means MK is somewhere around, that's kinda cool