Absolutely. Who is to say what is considered "normal" (to walk 8 miles back to base) that he isn't doing exactly the same thing on all those occasions, something his family and friends don't actually know anything about, they just consider it a normal practice because he leaves and then turns up the next day (on every other occasion). Only this time it didn't work out as planned. They haven't really said "why" this is normal for him, by which I mean, there's no indication he actually enjoys hiking or anything that would relate to a desire to walk that far, at that time, on any occasion - really.
It isn't normal to sleep in a doorway, no matter how many times that is preached. In my mind if he did that, it was to sleep off some booze so he could drive back, avoiding any walk. If he wanted to walk home, he would've done it straight away (ie after eating kebab). He's loitering with intent of some kind. I don't want to rip on the poor guy, but I think it's prudent to actually quiz his "normal" actions deeper as James King suggests. Sleep in a doorway and then skulk around some bins at 3.30am is not normal behavior in anyone's books, let alone a trained, regimental, routine driven serviceman. Even homeless people go somewhere they feel safe at night.