I'm wondering if Disney ponied up for a higher percentage of the music rights on this set, so there aren't glaring omissions like in Season 1. Not like they couldn't afford it.
Several songs/skits were left off of the season one DVD sets, most likely due to licensing issues for song rights, with the exception of a line from the Muppet Pitch Reel. They include:
Joel Grey - "Wayne & Wanda", "Muppet News"
Jim Nabors - "Gone With The Wind", "Danceros"
Paul Williams - "All of Me"
Charles Aznavour - "Dance The Old fashioned Way"
Vincent Price - "You've Got A Friend" (this really bothered me)
"Pitch Reel" - Kermit saying "What the hell was that?"