I'm afraid that making the rewards warband centric instead of Wizard based would turn the game into a kill them all style hack and slash.
Many people feel treasure may be flowing a little too freely. Awarding treasures that were not even removed from the table only makes that worse. It also encourages players to kill for Xp and roll for free treasures afterwards.
If you have lots of line of sight greater than 12", let alone 24, you are not playing with enough terrain density. If you played with more terrain, the range of line of sight spells wouldn't be an issue.