Yea i bought a hifi amplifier for 50 bucks at the pawnshop and a pair of speaker from the fleamarket. It works great

They might not self-identify as an audiophile, but they're definitely on the gradient. At high (and even medium) levels of the game, musicians, producers, and mix/mastering engineers are often using >$5K headphones and >$30K speaker setups, and that's not to mention the cost of building & treating the studio.

These are people with deep love for music, and many of these same people have high-end listening systems at home as well. I've had the joy of listening to some really nice setups, and it's definitely hard going back to my home stereo afterwards.

Where I think it veers off into pseudoscience is once you get into the stratosphere of >$100K setups. At that point it's marginal (often indiscernible) gains that are exclusively marketed to people with money to burn. People who just want to know they're getting the absolute best of the best, regardless of whether they can tell the difference. There's a lot more marketing than reality at that level.