Like I said before, it isn't just Disney. Let's put the blame where the blame is due, Don Sonyone. Disney is apparently allergic to giving any of it's standard DVD's any special features of any kind, and it's treatment of the Muppet movie is no different from their bare bones rerelease of The Lion King.
Welcome to the Muppet Central Forum!
Christmas Music
Macy's Thanksgiving Parade
Sesame Street debuts on Netflix
Back to the Rock Season 2
Sam and Friends Book
Jim Henson Idea Man
Bear arrives on Disney+
Get it? Rowlf! Ahhh, I'm so fun-nee! Wocka Wocka! 

LOL!