Old Guy Convention
When a bunch of old guys gather at a McDonalds, IHOP, OCB, or mall food court to eat breakfast and bullshit for a long period of time. Only groups of 5 or more qualify, as this signifies that at least two transportation vehicles were used and a greater level of coordination was involved. I know you can technically fit five people in a car but would an old guy ever ride bitch? Since the elderly enjoy pattern and familiarity, these conventions can occur weekly or even daily in a single local.
You'll never get a seat at McDonald's on Thursday mornings, the whole place is an old guy convention.