Mix the olive oil, seasonings, salt and pepper together in the small bowl. Reserve some mixture for garnish. Pour the balance of this mixture over top of the octopuses. Cover them all evenly with the mix, rubbing it in with your hands.
Turn the barbecue to high and allow it to preheat for 20 minutes. Place the octopuses on it evenly, spreading them around so they do not touch. Roast them for 3 minutes on one side and then flip them and roast them for 3 minutes on the other.
Remove the seafood from heat, plate, drizzle with the reserved oil mixture and serve immediately.