They are simply looking for a way to appease the Palis and to bolster Fatah compared to Hamas, now that the two are openly at war over Hamas' taking over Gaza. It is dumb and would not work, but that is all the motive there is to it.
A better approach would be to immediately blockage Gaza and prevent all entry of anything. But they instead sit and take daily rocket attacks, and let the agencies ship in food money etc to support Hamas and their new subjects.
Thanks..eom