Whenever I read a story about the various Mr and Miss Buttinski, well, butting in where they are neither invited nor wanted just to be rude or cruel, somehow I'm reminded of my elementary school.
When a classmate started badgering you, we used to say "[classmate's name], my grandpa live to a hundred years, do you know how? He minded his own business"
Of course, we didn't actually mean it as a threat - to be honest, I'm not entirely sure we grasped the implications, it just sounded witty to us.
Anyway, on a scale from 0 to 10, how rude do think it is?