Because the most important story of the last decade was bound to have a weed angle:
"Osama bin Laden's Abbottabad compound may have appeared no different from any other nondescript house in the middle-class neighborhood of Bilal Town, except for the high cement walls topped with barbed wire — and a few other distinguishing factors. Along with rows of cabbages and potatoes on the border wall of the compound, for instance, CNN's Nic Robertson discovered rows of marijuana plants."Take it away, Vulture via Daily Mail UK.
"The discovery raised the possibility that Bin Laden may have been a regular smoker of the 'weed' strain of the plant. ... Bin Laden had in recent years suffered from kidney problems which may have been eased by taking marijuana for its medicinal properties."