It seems to me, and I could be wrong, they are kind of a Montana tourist thing. Not that locals don't enjoy them, because they do, but it seems like every time I see them, it's either in the Airport in the "Montana" section or in the "Montana" section of the grocery store or a local gift shop.
When was the last time you cleaned out your medicine cabinet? The public can bring unused, unwanted, or expired prescription drugs for safe disposal during this event.