They gave it to him because he is the story line on Smackdown look back over the last few months whois smackdown focusing on besides Triple H is going back to Raw with the WWE Championship so they had a dellema how do they get the World Heavyweight Championship on Smackdown? Well Edge is known as the Ultimate Opportunist. Besides who else could have pulled this off? So he was the only choice. Simple wrestling psychology. Duh!