I don't remember seeing this when the Monkees was first run on TV but, as a 10 year old, I must have seen it. I watched the Monkees religiously. Zappa's appearance didn't leave an impression on me then but it sure resonates today.
While his death triggered memories for me and probably every other North American in their 40s and 50s, it wasn't unitil I saw the comment below that I began to reflect on how the Monkees influenced my musical taste.
I remember putting up posters of the Monkees and the Beatles on my bedroom wall; begging for guitar lessons because of the Monkees, even though I had fought tooth and nail to quit piano a few short years before. I had all the Monkees' records. I even found out that they didn't write their own songs or play their own instruments and I really didn't mind, at first.
I loved the Monkees.
Then they sucked.
It was a rite of passage.
While I was trying to shed the fun goofy music of my youth for the serious deep and meaningful complex cool stuff, the people actually making the music were far less worried about what was considered cool.
Obviously Zappa put the Monkees in the proper context earlier than I did.
Obviously Zappa put the Monkees in the proper context earlier than I did.