Additionally the lossless, compressed tracks can actually offer higher sampling rates than raw PCM, because there is a max-bitrate allowed for an audio track. At 192 kHz, 24-bit, with 6 channels (5.1; the sub-effects channel still has to be stored as full-range) PCM would exceed that, but TrueHD and DTS-HD MA with their compression can stay under the limit.
Think of it this way. What's better downloading a ZIP file of a document and unzipping it, or downloading the document straight? They are both the same in the end, because the ZIP file compression is lossless.
