Haven't seen this yet, but apologize in advance if already discussed...
While listening to the Vanished podcast for my first introduction to this case, I understood his sister to say that it was odd for Chip to be at that Circle K, because of the distance from his home. It's about 2.9 miles so a pretty good walk, for sure. However, this is the same Circle K he was leaving when he got into his accident two months prior...almost to the day. The cause of this accident was sited as a diabetic emergency. Meth, if taken by a diabetic, would cause a rapid acceleration of the burning of carbohydrates in the body, sugar being principal among these, and quickly lower the blood sugar levels of even a non-diabetic individual. Losing awareness, motor function, and even passing could result.
Was Chip just familiar with this Circle K, liked the workers there, and frequented it as his regular convenience store...or maybe it was a marked drop site that he had used/been instructed to use for some time.
Devil's advocate- let's say he had used Meth and this was one of the reasons he was in the bathroom for as long as he was, and forgot the bags he had carried in...
when driving, the effects were clear resulting in his accident.
when walking or getting a ride similar effects but a much more private result, perhaps even his ride panicking and disposing of a body rather than bringing further "trouble" on themselves. Or perhaps disorientation led him to end up in a place he couldn't get out of.
I haven't read a clear explanation of what, if anything, the dogs picked up around that Circle K. Have I not paid enough attention yet?