I'm not a camper, but I don't find it unusual at all that ggp was along. I do find it unusual that IR was also along, since DK and JM had never met him and I would not think ggp would need a friend to entertain him, since he had his family. They all came from Idaho Falls, so I would think the family could drive ggp's truck and camper, leaving DK's truck at ggp's house. Maybe they were all expecting to come and go at different times, but that would mean IR would be expected to look out for ggp when the family wasn't there. In fairness, before I saw the doorway interview with IR, I wouldn't have thought his presence was so strange. But IR doesn't seem like a great conversationalist, doesn't appear to be capable of caring for ggp in DK and JM's absence, and wasn't needed to drive ggp's truck if the family have driven to the campsite together, so I don't understand what he added to the camping trip.