Yes, it would hurt because the bricks would still have the same mass.
While the weight of the bricks would be less on the Moon due to its lower gravitational pull (about 1/6th of Earth's), the mass remains the same. If you were hit by a ton of bricks (which has a mass of 2000 pounds), it would still have the same mass on the Moon, and therefore, the impact would still be significant enough to cause injury.