Plain common sense would dictate that many people would be happy to earn a specific amount and stay where their roots, family and friends are. If the only people you know would up sticks and move anywhere to spend a large portion of their life where a few thousand more was available then you must know some seriously sad individuals. Even your football example is off. It's a short term career where the amount a player earns has to be maximised as they have zero transferable skills and may have to live off what they earn now till they die. Even then you only have to look at players that opt to live in London over Manchester because of what each city has to offer, or in Dimitry Payet's case taking a massive paycut to move home to France, to see that your earning capacity isn't the be all and end all to a lot of people. This is why other countries in Europe don't have such enormous differentials in pay between top and bottom. Why aren't there people flocking to America?