Strangely enough I've found myself on the wrong (illiberal? UKIP?) side of UK immigration debates because I feel compelled to point out that "reasonable people" (e.g. sensible economist Jonathan Portes) are building their economic case for immigration precisely around this:

Yes, there are winners and losers, the theory went, but the winners can always compensate the losers, so that free trade (or even freer trade) is a win-win.