The obvious answer being, of course, "because we live in a society structured such that the rich and privileged tend to pass that on to their children, allowing them to take the time to be Olympic decathletes, friends with presidents, and famous men of letters."
I'm not at all surprised about the recent interview in the Times of London with Gore Vidal, where he predicts a dictatorship in the US and says that Americans "don’t have any thoughts, they have emotional responses."
This is, basically, the flip-side of the nuts on the Texas school board who want textbooks talking about creationism and southern pride. America is caught between our native aristocrats on the one hand and a vast anti-intellectual tradition on the other. It was reflected in the original design of the House and Senate with the House being elected directly by the fickle people for 2-year terms and the Senate being chosen by the state legislatures. And, to some extent, this is still the case. Political dynasties tend to be in the Senate, after all. But Vidal's contempt for, say, every American not fortunate enough to go to Phillips Exeter Academy is toxic. It's the kind of thinking that leads to, among other things, fascism.
When the elites take the contemptuous view of the rest of the country, we end up with demagogues wielding massive influence over factions of the population, and the "well, they deserve what they get" attitude from Vidal doesn't help. Fascism doesn't just spring fully-formed, it grows out of the cracks in public trust, which Vidal is helping to expand.