Lasers vs Phalanx
Sure, projectile interception *can* be done using currently available defense guns like the phalanx, but its a very complex task indeed compared to painting an incoming projectile or aircraft with a beam of light.
Should this device do the job, its targetting hardware (of the mechanical pointy type, computerised calculation type and radar tracking type) would conceivably be an order of magnitude simpler. Interception rates should rise significantly.
That's the major selling point here... not dropping dud shells onto the surroundings is a minor bonus in comparison.