Beautiful area, but camp at own risk

This trail has campgrounds near the base where you can stay for up to 2 weeks. This is first come first served and leaving your camping supplies; tent, sleeping bag, chairs, at your site is supposed to mark that this site is taken. However my girlfriend was just staying at this campground when a family drove their pickup truck and a bus onto her site while she was gone, claimed it for themselves, stole some of her supplies and then lied about it to her face when asked. This shouldn't happen. Rangers are supposed to patrol the campgrounds in the area and help enforce regulations and keep everyone safe. However she had been at this campground for over a week already when this happened and in that time never saw a single ranger come through. In the end she was forced to leave without getting her stuff back and cut her trip short, not feeling safe camping near thieves. The forest services really need to do a better job, campers shouldn't have to worry about their campsites or possessions being stolen.