
Continuity mistake: When Clay and Jenna leave the lodge and walk over to his motorbike Clay has his bag on his left shoulder. In the next shot it is instantly in his right hand. Then when he sits on the bike the bag is still in his hand, but in the very next shot it's suddenly back on his shoulder. (00:37:55)
Chosen answer: When Jason brought her brother's backpack, you can see a small table next to the mattress with some bottles and cans, there is also something what looks like bag of chips (or maybe marshmallows?). I'm sure that he knew that she needs food, and brought her something from campers or cabins.