Anyone know WHY it hasn't been released on DVD?

I think it's a simple thing like the first season did not have good sales. I'd like to see Shout or some other company release them as manufactured-on-demand discs. People who love and appreciate this phenomenal series should be able to see all the episodes on home video. It's long overdue.

No, it has nothing to do with the music. Twentieth Century Fox/News Corp owns the rights to the show. MTM sold the company to a British company, who failed miserably in doing anything with this series and several others produced through MTM. Then 20th/Fox gobbling it up. Between MTM’s ownership by the British company TVS Entertainment and it was eventually purchase by News Corp., the company and its library were held by Pat Robertson’s International Family Entertainment at one point but then sold back to 20th Century Fox. You always see television shows go into syndication after a few years on the air but I don't remember ever seeing it on TNT or the other cable channels that air older series.

Unfortunately, this happens a lot and its a twisted game. They have only released all seasons of Mary Tyler Moore and Remington Steel, all other series produced by MTM were held hostage, Rhonda (eventually released through Shout! Factory), Newhart, The Bob Newhart Show, Lou Grant, The White Shadow, Hill Street Blues (was released on DVD through Shout! Factory, and they finally released the last season in January, 2016 for Region 1 only.) I doubt that 20th Century Fox will release them anytime soon. Lou Grant a show that won multiple Emmy's has finally been released on DVD by Shout! Factory with Season 1 being released on May 24, 2016 and Season 2 will be released in August, 2016. The only reason I can figure is that they want to hold back so the demand gets higher and they can charge higher purchasing prices.

I read an interview with Blythe Danner who did an interview for the Season 2 DVD, she did a behind the scenes interview for whatever company that had plans to release it on DVD, and it never happened. It was one of my favorite episodes The Women. Unfortunately for fans this isn't new. Fox has done it before with The Bob Newhart Show. They had a deal with Amazon, worked with them on setting a price and Amazon put it up on their website for customers who wanted to pre-order it. Fox kept delaying the release date until they finally pulled it from being release. Amazon was forced to send an apology to their customers because of this little game they like to play. I will never understand why Fox wants to play these games. It's stupid and I have refused to watch any show or movie they release until they stop with these idiotic games. They did finally released all seasons and a box set.