Why Gummigoo is important
Caine's remark after first killing GG is a statement about mixing up humans and NPCs could lead to trouble. In the next episode we get our first glimpse of Able, an NPC designed deliberately to get into the player's inner circle. Able, likely using an AI system similar to GG's, is able to pass off as a human and drop hints about the players needing to respect Caine, hoping that such a thing would make them realize how much they like him.
Caine didn't delete Gummigoo to "keep track", he deleted him out of envy. Gummigoo had managed to do, in one afternoon, what Caine was trying to do for 30 years.
Bringing Gummigoo back for Spudsy's was a deliberate attempt to break off his and Pomni's relationship. When this failed episode 6 showed him in the same place as abstracted players like Kaufmo and Scratch; as Pomni's "first lady" in President Pomni and in an ad snarkily remarking "[he's] what you're thirsting for".
THIS is why the show kept reminding us of Gummigoo; because he's living in Caine's head, rent free.