Another stabilizing factor for the US dollar is that people, businesses, and governments need dollars for everyday transactions. This leaves a relatively small percentage of dollars available for speculators to trade. Bitcoin doesn't yet have this same level of stable demand, so is at greater risks for speculative bubbles since such a large share of Bitcoins could be acquired by speculators.
Well comparing bitcoin with dollar,euro or any other currencie makes no sense,bitcoin has the community support,but as you stated most countries use dollars to every transaction they make being import or export,soo bitcoin as maybe 0,01% of total money over the world.