Interesting that you and I have such a different take on this.
From the quote from ER of "he would let me know where he landed for the night. So like, if he was hanging around with his friends in Bayfield, you know, he would let me know what friend he was sleeping with that night", you get that he would not touch base, and I see exactly the opposite, that he WOULD touch base and say which house he was at that night, not the next morning.
From the statement of a friend that he got a ride home home for the entire group by sticking his thumb out one time (not multiple times, just one), but his father SAYING he had a history (which has not been substantiated) to you makes him a habitual hitchhiker. History to me is "An established record or pattern of behavior", not a one time event. And grabbing a ride in the snow with your buddies is considerably different than picking up a ride by yourself when you know your ride is coming. (not to say that it couldn't happen, just that there was no history of that)
And while I do agree that it's not uncommon for a couple of hours to pass between the last time a teenage child was seen and a missing person's report, I find it a little uncommon that a father knows his son wants to visit friends in another area, that he is supposed to be the ride, and thinks nothing that his son is not sitting there waiting, chomping at the bit to get his ride. I trust my son to make good choices, but I'd still check to see where he went if I knew I was supposed to drive him somewhere. Otherwise, I would be shirking my responsibility. To just go, "Oh, well he's not here, now I don't have to drive him so I'll take a nap." would not be on my particular radarscope. But that may be because I have a 13 year old who behaves a certain way and I would know what would be odd for him.
It's so weird that two people can read the same thing and get two different impressions out of it, but there you go.