Tell me, what sounds so unlikely about this story? There isn't any element there that makes me go "no way in hell that could have happened". People routinely do dumber things, why couldn't a first-time camper owner set cruise control and get up from the driver's seat? It's not suspending critical thinking, it's just considering the chances. Such an even wouldn't even be newsworthy for anything but the local paper (just another RV in the ditch, nothing really exciting about this one), so the only way the story could spread is by word of mouth (remember, most examples from from before the Age of Internet).
Word of mouth, of course, being a known reliable source for everything.
Look, these sort of stories are just that: stories. While there's nothing in there that is outrageously impossible, the simple thing that there is no real evidence for any of this actually happening with any sort of frequency kinda puts it all into doubt.
Bottom Line: Always check your bull**** filters. If a story seems really really dumb, chances are it's either been exaggerated in the telling, or made up entirely.
