Shouldn't this go without saying? No, no it shouldn't — because anyone not in the military buying smoke grenades is probably a dick to begin with.
So, to reiterate: don't be a jerk while using smoke grenades. This includes rolling a smoke grenade into a nursing home, putting one in your professor's pants, giving your girlfriend an active smoke grenade for Valentine's Day, serving a smoke grenade for lunch, throwing a smoke grenade at a baby, etc. [Reddit via BuzzFeed]