At Maine's Baxter State Park, home to the trail's final summit on Mount Katahdin, officials say thru-hikers are flouting park rules by openly using drugs and drinking alcohol, camping where they aren't supposed to, and trying to pass their pets off as service dogs. Hundreds of miles away, misbehaving hikers contributed to a small Pennsylvania community's recent decision to shutter the sleeping quarters it had offered for decades in the basement of its municipal building.