Is that ripping them off though? I'd say Audiophiles want to pay over the odds for things that might not even really make a difference if you actually measured it. It's part of the enjoyment for them.
Just because someone believes a con job doesn't make it less of a con job.
[1] https://blogs.sciencemag.org/pipeline/archives/2015/01/29/ex...
(links to paper)
Motor function is objectively measurable. "I like the sound of this" is not.