The tire pile is a common element of Far Cry 3's junkyards.
Tires, perhaps taken from all of the rusted cars strewn about the island, have been stacked up into two piles and left, hubcaps intact, lying around on the ground.
A common method of execution in many gang cultures, specifically those of South and Central America and indigenous peoples of several pacific islands the likes of Rook Island, involves binding the victim in between one and three tires to prevent their escape before dousing them in gasoline and setting them on fire. Thus, with the high gang and pirate populations of Rook Island, it's not unlikely that similar methods are used here.
