I had my 5 year reunion last summer... I hadn't seen most of my high school classmates since graduation day.

I didn't wear my pin, but I did wear my lavalier. One of my friends had gone Kappa Beta Gamma at her school, but no one else was greek (or if they were, they didn't mention it). I did get a lot of the You joined a sorority? type comments though... but then again most of my classmates didn't go to college, so I think they all have the "Dying to Belong"/Animal House image in mind.