Those successful at trading guns for dollars are not expecting the dollar to remain a static store of value. They’re reinvesting or using the money gained from the sale, and dollar is just a medium of exchange. After the exchange, the money is used in ways that are dynamic with respect to the dollar. If the company were to throw dollars in a storage bin, it would be constantly losing value.
IMHO, there are 2 main types of inflation in gun prices. The first in an increase in the relative value of the gun caused by supply and demand. The second is an increase in the amount of dollars paid, caused by the deflation of value in the dollar. The second type of inflation has outpaced the first (excepting certain types of guns that are politically vulnerable, more comparable to the futures market, and the "bubble" aspect of gun prices)
Problem is, how to define "value" as a constant if we want it to reflect "what we get for the work we do" . A unit of value could be derived from average income to form a baseline, but why bother when there are commodities? The price of durable commodities remains roughly constant, compared to the percentage of average income it would take to buy them.
And the gubmint CAN print more dollars as "needed", which increases the supply and drops the value in them. It’s called increasing the debt limit.
The holders of the debt hold up the dollar’s perceived value … if they become overconfident in the dollar, and then lose confidence … it’s "dollar bubble" time.