Doesn't make any sense in the story. Jake is happy to give you the ASAMs because most people don't care or understand. When Old Paul joins, Jake tells you that this is the first new settler thanks to ASAMs. The only other people who actually used ASAMs got destroyed by gunners. It simply doesn't work to have settlers already have them.
And I'm not even gonna go into the morals of your sentence.
But as I said earlier I would not be against getting some vendors selling boxes but I think I could have an idea that would fit well in story. The supermutant who is willing to trade chalk for individual ASAMs could also sell boxes but, seeing he's hoping to get chalk for his headaches, he'd be selling them at an expensive price. It would also make dragging your ass back to this unmarked location worth it more. Right now, going back there to trade my 3 chalk for 3 ASAMs really isn't worth it.
But there are situations where I would be happy to overpay for ASAMs if I can get 20 or 40 in one shot.