Apparently, the FBI hasn't talked to this clerk yet, or he wouldn't have told the media anything, either. I'm sure they will be.
Question for you or anyone that knows anything about explosives -- I know nothing. What would a directional device do with a bomb?
Apparently, it wasn't a story until the FBI brought a photo of Hinrichs to the Feed & Seed, asking if JHIII had been in there recently. The clerk remembered him, thus there is now a story about it.