A "pretend irritable" remark that you eye-twinklingly snap at a fellow townsperson to humorously say, "Hello again" when you happen to bump into him a second time that day. A variation of this tongue-in-cheek greeting is, "We GOTTA quit meeting like this!"
In "Forever Young", Jamie Lee Curtis;s character smilingly quips, "Hey, quit followin' me!" to Mel Gibson's character on a couple of occasions when she happens upon him while he's merely sitting/lying quietly by himself.