If these people are thieves, why don't they charge double their retail price? Simple economics: the price of anything is what people are willing to pay for it and what they are willing to pay goes up if the product is scarce and down if the demand is not high enough. No manufacturer would invest in the machinery and labor to make a $250,000 speaker system if there was no market for it.
Gullibility is not a factor.
Gullibility is not a factor.