So, I learn from my Sis that a shopper scored an item from the yard sale for a 5-spot, plus a wild salmon the guy has just caught. "How much is salmon per lb.," I asked. "Might be $8.99 on sales," replies Sis.
So, a 20-pounder used in barter, yielding fillets at $8.99, Washington-state style, comes out to more than $150.00. Wow. Good deal for the fisherman -- salmon running non-stop off coast of the island -- not to mention good deal for the yard sale folks.
THEN (and check out sign below from my local supermarket) Wild King Salmon here in the Heartland sell for $16.99 per fillet-pound.
Lesson and Market Moral? Availability of something, like seasonal running of wild salmon, and its possible over-abundance, determines price --per item, per Pound, per sign, per whatever. You sure don't need government regulation here when it comes to pricing -- product safety, freshness, and quality, however; that's another matter.