We've had the same problem here in Iceland over the past 3 years, and it's only getting worse. We (the locals) call them "toilet paper tourists". It's a classic example of what economists call ´externalities´; i.e. great for the camper van companies (they make "shitloads" of money, pun not intended), great for the toilet paper tourists, who have a vacation on the cheap, but the cost is dumped (again, not intended) onto innocent 3rd parties in the form of degraded environment and diminished experiences. Oh, and good for importers of pot noodles and cat food.