Pavements (sidewalks to some) are littered more easily than they can be inscribed, but the former can provoke the latter.
Be warned: using chalk to broadcast a message may seem harmless, but previous posts on this blog (see links below) have shown this not to be the case. Some people may more readily take offence at pavement chalking than dog mess or random chewing gum.
The image below is of artist Ben Wilson who paints on pieces of discarded gum. Apparently he was arrested, something British cops like to do if someone seems a bit strange to them. BBC video here.
Previously:
Pavement chalking: this time seen in a positive light
