"It should NOT be unusual that this guy doesn't report everyone who asks."
It's been strongly suggested in the past, and is policy at many farm supply stores here in NC, to question anyone unfamiliar that attempts to purchase large amounts of ammonium nitrate.
I've seen enough photos of the guy, Hinrichs, to know that he wasn't your typical farmer type, and in fact looked a little schizoid in every picture I saw.
No one is saying that every single purchase of fertilizer is to be questioned, but this one had to have stood out. It should have been questioned and reported.
I love it here in Oklahoma, but I have to say, a lot of farmers look weird. I wouldn't want to have to be in that clerk's shoes and have to decide who I should report and who I shouldn't. I might be on the phone every time someone came in asking for AN. (And yes, some do wear cammos, more or less often depending on if they're doing some hunting after they put in the order for fertilizer.)
Also, according to one Freeper who saw the report, an off duty policeman was in the place and supposedly took down the guy's license plate numbers. Could be the clerk felt it was under control.