I live in DC and I'm 27 and I wear my letters mostly to workout or when doing something outside. My boyfriend also wears his on occasion. I really don't see how its different than wearing any other college shirt?
I also didn't know that DC now has the fashion police... I'll have to remember that next time I'm near Howard.. haha.
I do have to say that I do love to count the Greek intern's on the metro in morning during summer