Well, you're about a hundred years older than I am, so I'm pretty sure I would have experienced The Muppet Show in reruns. I was more of a Fraggle kid, but at the time I appreciated that those shows weren't shoving kindergarten crap down my gullet every five seconds. Honestly though, most of the adult jokes would have been way over my head, so it would have been the sight gags that did it for me.
Also, that insane mash-up Christmas special that has every Muppet in existence is one of the greatest things ever.