Sidewalk Chalk Was a Bust

So I thought I'd try something today and ended up getting yelled at by a shop owner.

I took sidewalk chalk and was putting "Support American Cancer Society" with my link. I thought I was far enough away from their pickup window, plus I though sidewalks were city property (I Googled it and it is) but she made me leave and poured water over the chalk. It was worth a shot. I thought near a popular cheesesteak store on game day would be high traffic.