Diner Rat, unlike the similar but deragatory diner whore is usually used by the deziens of the diner to describe themselves. Often found in New Jersey where there is really nothing else to do, except go to the diner. Diner Rats all tend to know the other diner rats from their respective diners. Often there is a form of heriarchy based on how long a "rat" has been going to the diner or how often they are there.
Spending hours at the diner tends to lead to intense or comedic philisophical disscussions or tales that everyone already knows ie. No Shit, there we were.
Usually the diner rats know all the waitresses/hostesses and have their personal favorites.
Often ordering naught but coffee and water the rats usually leave a substanital tip occasionally equal to or greater than their actual bill.
Diner Rat 1: Why are we always here?
Diner Rat 2: We're diner rats. It's what we do.
Diner Godfather: Guys chill we have to plan for the zombie apocalypse.
Tourist leaving diner: Those guys have been at that table since befoe we got here.
Diner rat overhearing conversation: oh good everyone else is here.