One of the things I love about Parks & Recreation is its sense of continuity. The writers have created a mythology for Pawnee and its citizens that makes everything just a little bit more real, albeit also more ridiculous. Running gags like the terrible history of Pawnee, often depicted in its murals, absurd media personalities like Perd Hapley, and the utter horribleness of the library show up in bits and pieces; while any given bit may or may not be a winner, they have a cumulative benefit to the show.
For instance, when you watched Season 3’s Ron & Tammy Part Two, you probably noted Ben Wyatt’s preference of calzone instead of pizza, and how absolutely everyone thought that was a terrible idea. Maybe you didn’t come away from the episode thinking “Hey, I hope Parks & Rec explains more about Ben’s attitude toward Italian fast food,” but then, BAM, this week comes along and gives you even more about Ben’s attitude toward Italian fast food and how it’ll lead to financial and personal success, and it is awesome.