If you’ve been in downtown Chicago this summer, you’ve seen them: ten-foot-tall metal pylons containing a glass-encased city map on one side and an ad or cultural announcement on the other. In recent months, 75 of the information signs have been installed on sidewalks throughout the Loop, paid for entirely with ad revenue. So what’s the problem? According to Chicago Tribune architecture critic Blair Kamin, placing ads on the signs cheapens the public streetscape. I couldn’t disagree more.