Synopsis
Two interesting observations about Scooter's debut.
His entrance is in conflict with the Muppet Movie which shows him being the Electric Mayhem's road manager and Muppet Babies where he grows up with the other characters. While some fans lose sleep over this, this is hardly a serious contradiction as we're reminded throughout the Muppet Movie that it is just a movie, one with an alternate "history" (indeed if the films were to be taken at face value, they all contradict each other) and the Muppet Babies is also to be thought of as "just a cartoon" BASED ON the characters. The babies' Muppetized debut in Muppets Take Manhattan was part of a dream sequence. (But then there's the home movies of the Muppet Babies the Muppets watch in Muppet Family Christmas, Scooter included, but don't lose your head pondering this).
This is episode 6, and Scooter's already appeared in episodes 1, 2, and 4! The first two episodes were shot before the rest as "pilots" so obviously the writers thought once the character was established that it would be fun to explain Scooter's entry. If it helps, think of this as somewhat of a "flashback" episode. A number of early episodes didn't include Scooter in them so they could be aired before this one as to not cause confusion. (Indeed, in some markets the Scooter-less Rita Moreno episode was the debut, but in others the Jim Nabors show was the second to air after the Sandy Duncan one which included Scooter.
Since the Muppet Show was in syndication, meaning that episodes might air in different orders in each market, the writers probably didn't worry too much about this. Annie Sue's "debut" episode in season 3 also aired after the audience had seen her, and was also done after the character had been used.
The original name for Miss Piggy was Miss Piggy Lee. This idea was quickly scrapped though the first Muppet Show Annual refers to her as such as well as a few articles around the time. The Talk Spot in this episode is the only time in the series where Piggy is addressed as "Piggy Lee".