Regular people have no idea what kind of loopholes exist for the super rich.
Here's a simple example.
A couple filing jointly can put up to 34k (17k each) into a 401k, and the taxes are deferred. Most people can't do that.
So the benefit of that tax break goes to those with higher income. When I told friends that my wife and I can do this because we both have high incomes, they are blown away.
Most of them don't know that each year, I get a raise, when my salary passes the Social Security cap. They pay SS tax on 100% of their income, and I don't.
I have some stocks that pay dividends. And those are taxed at 15%. So if I make 10k in dividends, and a blue collar worker friend makes 10k moving furniture, his 10k gets taxed at a higher rate.
So I get a couple nice tax breaks ... but I'm sure that Mitt's tax return would blow ME away.
I suspect that he can create a shell corporation in the Caymans, "invest" in it ... and then manage the money such that he pays little to no taxes. That money becomes part of his estate. It goes into tax deferred trusts. And it will pass with almost no tax to his heirs. And they will never touch that money either.
All legal. But if the average American got to see his returns, they'd flip out.