Here's why it was included:
* Humor: The bar's name, its clientele, and the bizarre events that occurred there were primarily meant to be funny and over-the-top.
* Social Commentary: The Blue Oyster Bar acted as a stand-in for the unsavory parts of society that police officers often had to deal with. It was a way to poke fun at the weird and unexpected aspects of their jobs.
* Character Development: The Blue Oyster Bar provided opportunities for the characters to demonstrate their skills, even if it was in comical and unconventional ways.
* Plot Device: The bar was often used as a setting for important plot points or comical situations that moved the story forward.
The Blue Oyster Bar, in short, was a running gag that served multiple purposes in the Police Academy films. It provided humor, social commentary, and opportunities for character development and plot advancement.