We do not want to rely on a regulators. We want to sink the minimum variable curent required by music from the local capacitors because that current can be very fast. If we starving local capacitors, we will rely on the first capacitors which are bigger. The chain up to the output stage will be more longer and more slower. The result is a "flat" sound, uninvolved. That's what we feel in our ears. So, maybe we do not hear the noise from the couch but we feel the flat sound.
If you want a minimum noise, low resistances, then you must have a very hefty power supply which mean much more money. In our case, we must to buy an expensive DAC with hefty power supply and output stage.