I went to a gun show this a.m. and brought along a bunch of surplus (to me) powder and primers.
The primers sold in about 10 minutes and most of the powder in 2 hours.
I was charging what a local shooting supply was advertising (but they didn't have any). No gouge.
I watched one guy walk out of the show with 20,000 primers at a MINIMUM (cheapest available) price of $400 a case. Several others walked out with a couple of cases.