You smoke your weed and take the pill. All you have left is half a gram of that nicely potent opium. A couple weeks have passed since you traded for the drugs. But one morning you wake up and go to your living room and there's the Necromonicon. It's back on your fireplace mantel!
Its like a damn hard bound boomerang! You wander how many times you can sell or trade it and have it appear back on the mantel?