Zingerman's offered me 10 percent off when clerk saw my WCBN t-shirt.

I'm sure it's not a standard discount. I had friends in town who wanted to be able to say they had gone to Zingerman's Deli at Kerrytown. Walked in and the Pretzel Guy said "You, sir, can have ten percent off your order today for wearing that WCBN t-shirt."

Get one. :-)