Some photographers in Toronto, ON have used the ever-popular colored smoke grenades for some sort of video/photoshoot, leaving behind a deep red stain on a beautiful marble archway, and were even careless enough to simply leave behind the grenade instead of taking it with them, which brings me to my point: we need to be better.
I'm sure we've all used these smoke grenades at some point. They're trendy, fun, and (relatively) harmless. However, they can stain buildings, rocks, and clothing. While it's easy enough to clean up right away, we need to be extra mindful when firing these off on property we do not own.
Photographers can sometimes get a bad rap for being disruptive, messy, or rude. While most photographers I know are anything but, there are definitely some bad actors out there, and we need to be active in calling out people we know who leave refuse behind. There is a great quote I heard: "take only photos, leave only footprints." It is something of a mantra of mine when outside of the studio. With things like smoke bombs, they can be used outdoors with little to no issue; however, we need to be sure to wash off immediately if we accidentally leave a stain and take our refuse with us when we're done.