I wouldn't be surprised if they bought any of the stuff they "bought" at all. From my very limited experience in the unreal TV business in a similar genre, prices were negotiated, deals struck...and then the original owners returned home with the stuff they brought - but the whole buying/selling transaction looked GREAT on TV!
When I was on LORDS OF WAR I brought two uniforms from a couple who meant while in the service in WWII. She was a WOMAN MARINE sgt and he was a NAVY officers. The producers decided my $$350-400 pair of uniforms was worth $600 and that is what they "sold for" during the staged auction, which was shot in three takes with each bidder whatever the producer told them to bid. In one of the three takes they shot me and the expert "reacting" to the scripted bidding. In the other two takes our mikes were turned off and we just mouthed the reactions.
Since all of the bidders were paid to be there and only made fake bids, I left at the end of the long shooting day with my uniforms (but how wish I'd had the $600 instead).
Checkout the authentic-looking militaria bidders - they were actually hired through an ad. The arrow points to the soccer mom "winner" of the uniforms.