You can buy ammonium nitrate in bulk. Much easier to turn into an explosive if that’s the point you’re making. Just say you’re opening a farm and off you go.
Well of course, but that only works once before you get traced and caught, might still be acceptable for the aforementioned crazy guy but I assume most others would rather blend in with the 50 million people buying gas on any given day.
I heard something about this too, though I omitted it for the sake of brevity. Don't know the specifics, but yes I think it's also a drug precursor. I remember some CCTV footage of people stealing ammonia from large tanks on a farm, not sure what other reason they would have other than drug production.