It is not a sales pitch. The original reel-to-reel studio recordings are, generally speaking, superior in every regard. If there is deterioration in the original tape then specific areas will be re-recorded by computer from another part of the tape that is not damaged. For the most part, the recording companies kept the original tapes in climate controlled storage to ensure stability of the oxide. Many of the 1950's tapes are still in pristine condition. Playback is usually done on an Ampex 350/351 tape deck, or similar professional deck, which is the deck most recording studios used. Listening to the original tapes is like being at the recording session itself, though it may have been 50 years ago.
"Cut from the original master tapes"
this is a phrase I see often when looking at new vinyl of old recordings. I always wonder if this is a good thing. I'm sure the tapes used are of a better quality than the 8 track, casette, or reel to reel tapes that I used but were they really of a quality that they would still be Quality today? Do they not lose their muster, so to speak, like everything that one deems to be from that period of time referred to as "In the day" (yours truly included)?