I think czarivey is correct, to a point. There are definitely some things on the $32K level equipment that are aimed more at luxery level rich people. However, the more expensive DACs do have elements that sound better. That being said, there's always a point of diminishing returns where you are paying a LOT more for a LITTLE bit of improvement.
For those of us who can hear differences, things like "quality of power supply, power filtering, power regulation, etc " (what dlcockrum said) become very important. Also, a brand-new DAC is not necessarily going to sound better than a 3-5 year old DAC. It entirely depends on internal components. For example, I continued to listen to a 15 year old Krell HTS (processor/DAC) using lo-res DolbyDigital/DTS because this still sounded better than new TrueHD/DTS-MA processors (even though it was hi-res audio through HDMI). I tried several processors and only was satisfied with the newer Krell 1200U. I am partial to the Krell sound (I don’t like laid back sound), but it is just an example.