I buy audio gear so it sounds good. I buy wine so it tastes good. If there is no difference in how it sounds, not just for me but for highly respected experts, as well as every impartial test ever conducted, then there is no reason to spend more money.
Well there are many reasons, but they are to do with aesthetics, how they make you feel, bragging rights etc. Not performance. And IMO, anyone who buys cables, power conditioners etc based on these criteria is a damn fool
If I was stinking filthy rich, maybe I'd buy a B&O cd player and designer speakers because they look cool, but I'd still never buy audiophile interconnects or any of the other crap they peddle in Sterephile mag etc.