Because of bitcoin's ludicrous generation curve the early adopters own what, 3/4 of all the bitcoins, guaranteed to be at least half of all those there will ever be? So yeah, price movements are likely to be their influence because they're the biggest owners.
>You also appear to assume, incorrectly, that early adopters are just itching to exchange out into fiat currencies, as if their eyes are glued to their computer monitors, just waiting for their lucky day to "cash out BIG" ... into fiat currency. Hmmmm
It only takes a few. They're sitting on these bitcoins that have shown themselves to be highly volatile, and at the moment their value is increasing by the day. Sooner or later many of these people are going to be in a position where they could get several hundred thousand dollars by selling up, if they're not there already. Is a crash certain? No, but it's wise to plan for that contingency.