The tarps were part of their base kit provided by the producers that they didn't have to select giving the participants more choice in the kit selection.
Those villages are pretty darn small - probably no bigger than a dozen homes belonging to First Nations and may not even be used all year round. Quatsino has about 90 people; Winter Harbour 20 people. Any decent location manager could have bought their silence and non-interference in a heart beat. Regardless the area is pretty remote. I don't think the area is used much by kayakers in the late fall but GE shows a large commercial fishing structure in the area and of course commercial logging in the area. The "park" is more of a tree preserve than an developed area and designated to protect old growth forest.