Think of it as the law of deminishing returns gone mad.
The audiophile players (or for that matter anything tagged "audiophile") generally tout specs "improvements" that cannot be perceived by human hearing. Once you get outside the range of human perception, it does not matter how far out you are, it will not matter.
For instance, all else being equal, a player that has flat FR between 10Hz-25KHz will sound no less flat than a player that has flat FR between 1Hz-100KHz, or all else being equal, for the same power at same frequency, 0.001% IMD will sound no worse than 0.0001%. But to achieve the respectively latter specs, the players will be orders of magnitude more expensive.
Also, there is a lot of BS going around in the AV review world. A $50000 "CD Transport" MUST SOUND BETTER than the $2500 "CD Player". A $1000/ ft "Speaker Interconnect" must sound better than a "$0.50/ ft "Speaker Wire".
For people with a lot of money, logical reasoning seems to be the first thing that they loose. That combined with bragging rights is what drives the "audiophile". For the rest of us (comparitively no money, plenty of brains) there is AH.
As stated before, there are several additions to the setup and room that provide considerably more palpable improvements. Eg. Speakers, placement, eq, treatments, etc.