Well, that's one side of it -- that grandpa's weed was low-grade and today's pot is high-octane.
But more than that -- there's a lack of knowledge about cannabis, and it's often assumed that all parts of the plant are high-inducing. I mean, I've even had people balk at a purse I have that's made from hemp. Like "wow, aren't you worried about walking around with that...?"
There are chemical compounds in cannabis oil that treat seizure disorders better than any FDA-approved medication, and with much fewer side effects. Most of those are free of THC, the intoxicating agent. They're being used experimentally in Colorado, and I've seen disabled children who used to be drugged into an almost vegetative state start talking, sitting, standing, laughing and seizure-free while on CBD oil. Outlawing that use would be cruel.
But that doesn't mean I'm in any way supportive of the willy-nilly "medical" use someone mentioned in another post.