While I absolutely disagree with James comment and its distastefulness; I have to say you're completely wrong.  There have been multiple instances of people killing over weed just this year alone.  Including the kids who shot the woman in the face because they wanted to rob her son of his weed and cash.  Then there have been the multiple shootings, and the attack via hammer, that didn't cause death (but did cause injury) from people trying to rob or having successfully robbed people over marijuana.  So people do "kill over weed"