I'm one of those "live" persons at the board of three TV stations, all automated, in one facililty. All programs, spots and promos are played from hard drives now, not tape. The volume is set when the files are created. Shows and spots are ftp transferred to our facility and there is nothing we can do about the volume. It's like watching videos on YouTube - some are louder than others. You get the volume as set by the creator. Well, there is something we can do. We could play the spot in real time and re-record it back into our system at the proper level. We've had to do that on several occasions until the production company could ftp us a corrected spot.
But, the main reason spots "sound" louder is the lack of dynamic range. On the VU meters all the volume peaks hit the same point, but on a show with dialog there is a lot of dynamic range - the difference between low and high volume moments. Spots are produced with a reduced dynamic range. The audio is compressed so there are no low volume moments. Even though the audio peaks at the same electronic level, the compressed audio will sound louder.
And as far as I know, nothing is exempt.