I have to say I hardly ever see runners in the street here and when I do they usually move over as much as possible. I'd never think of saying "get on the sidewalk" since I hear that enough myself, and they're allowed in the street anyway.
If I had bunches of them clogging up my lane I'd probably be annoyed. Even so, on the Greenway where I commute and sometimes run, even the big groups tend to be conscientious about getting out of the way. Maybe this is a cultural difference, Chicago vs South?