Can someone explain to me why : Accupahse Equipment is that expensive ?

From my own experience the Accuphase Class A amps (e.g. E-650 and up) are a significant step-up from Pass or Luxman: Much more refined and detailed with a more natural and realistic presentation. They also measure perfect. Besides amps, where Accuphase outshines Luxman and Pass is for the DAC (DC37) and the phono stage (C37).

Furthermore build quality for Accuphase is not matched - there is a reason it is legendary; especially in countries like Germany that are renowned for perfectionist equipment.

Pass is very good value in North America and features a warmer and relaxed (and sometimes slightly more veiled) presentation; unfortunately oversea the price for Pass also doubles, so this is not so dissimilar to Accuphase in the US.

Luxman is very good, especially for the competitive price in North America (with the reorganized direct distribution). The new series looks even better built than the previous. Soundwise they are good but did not bowl me over when I heard them last.

Esoteric has excellent built quality, closer to Accuphase, and a step above Luxman and Pass IMO; unfortunately, I have not fallen in love with the sound of Esoteric. Also worth noting: the future of Esoteric seems to be in questions with Esoteric/Teac's parent Company (Gibson) in bankruptcy.

I researched this about two years ago when I was looking for an integrated amp.  At that time, I could buy two Accuphase amps from Japan for less than the retail price in the US.  And that includes the shipping.
The distributor markup is exorbitant!  All reputable manufacturers maintain distribution and repair facilities whether their goods are imported or not so that is not an excuse for these prices.  Customs and shipping are also very little relative to value.
Plenty of companies (Leben is one) manage to bring their goods to the US market at prices very close to Japan.  Last time I checked Luxman's markup was about 35% over Japanese retail.  Can't help but feel that Accuphase must be indifferent to the US and European markets to have chosen such a distributor.
Luxman is only about 25% less than Accuphase in Japan.
In the end, I bought a Luxman 507UX demo here in the US and I have been very happy with it.  Wish it looked more like an Accuphase though.
Rolex is a charity.  That is why they are able to sell their watches at such giveaway prices!

If you want good stuff go with McIntosh. I have McIntosh pieces and they have a great solid "feel" to them. Every knob, switch has that same feel. And when they are turned on that "teal green" color and the blue meters is exquisite and sets them apart from everything else on the market.

if you have the space and budget, a second A-03 run in mono would likely solve you power deficit...