No link, since I've seen it all over the place lately -- actually, I've always seen this all over the place: it's the statement, usually made when someone claims that people in Profession X or Business Y or Avocation Z are not paid enough, that if they want to make more, they should just quit and go get a job where they're paid more. This is complete nonsense, and it is basically meaningless -- it's just a different way of saying "Oh, shut up".
Changing jobs isn't like changing brands of Raisin-Bran, and it's not a simple thing like it is to stop buying Kellogg's and get Post instead.
(That said, it's simply a fact that not every job is going to get paid what it might morally deserve. What's morally desirable and economically possible are often two different things. Take it from a guy who thinks that the person cleaning the grocery store bathroom should be making $19.00 an hour, but who knows he'd be laughed out of the room, and rightly so, if he voiced that opinion.)