A somewhat related story...
I did the Madison Gulf / Osgood loop this past weekend. When I got back to the junction of Great Gulf and Great Gulf Link Trails, I was approached by a group of young kids who couldn't remember which trail they came in on ("we crossed on a long bridge"). So I pointed them the right way.
Back at the parking lot, one of them approached me and asked if I would drive two of them to Gorham so they could get a cell phone signal. Sure.
On the ride up I learned why they needed to make a call. One of their group had dropped them off at the Great Gulf trailhead, then proceeded to drive up to the summit of Washington. I guess the plan was for the rest of the group to hike Great Gulf Trail up to Washington, and then they'd all ride down together. Except that this group didn't start hiking until 1:30pm, had no gear / clothing, no maps, hardly any water and had barely researched the trail. They got about halfway in and turned back ("the trail got really difficult"), unbeknownst to their friend waiting on the summit.
I gave them some strongly-worded advice against climbing Washington without the proper gear, research and experience, but I think it fell on deaf ears, as they were hell-bent on trying Washington again the next day. I also told them that should something go wrong, a rescue could be quite costly.
As with Huntington Ravine Trail, I suspect they saw a map of the GGT online somewhere and thought, oh, well, that looks like it goes right toward the summit, and that was it.