This thread again...
They're paid by the free market, the people who pay them are free to spend however much they like on players wages, since they're willing to pay it, they cannot be overpaid, by definition. And to get it out of the way before the argument comes up, no you cannot pay for 50 more nurses a week if we paid Rooney less, you can't take money from a club to pay for nurses, it's a stupid argument. If the money doesn't go to footballers, where does it go? Sits in the owners' bank account, untaxed, unspent, out of the economy. Without doing the tax calculation, Rooney's wage probably employs about 1.5 nurses per week in tax (let's not get into tax avoidance.)
Football is the most in demand sport in the world, a multi-billion pound industry, I fail to see why people don't expect the players who are the major attractions in that industry to be highly paid. Is Bill Gates, the major player in one of the biggest markets in the world overpaid?