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If you go into some Japanese stores, the clerks have fist-sized orange balls behind the counter. No, the are not for sale. They're balls of paint that clerks throw at robbers so that police can more easily identify them:
The orange orbs you observed are called bohan yo kara boru (anticrime color balls). Basically, they're paint balls — plastic spheres filled with brightly colored liquid pigment. But unlike the fun-and-games variety, these balls are kept on hand in case of a stickup. The idea is to lob one after a robber and mark him to improve the chance of an arrest.
Link via Urlesque
"Give me the money or I'll make you look a guy trying to rob this bank."
Put yourself in the shoes of the robber. If you see one of these sitting around in the target store, you don't know if the person is going to throw it. You pull a gun. the clerk does throw it. You shoot the clerk and are quickly apprehended b/c everyone (including the cops) knows what that color means. Thus you either choose another store or don't shoot (why add murder to robbery charge?).