I _have_ had someone on another continent charge things to my credit card.
Also, exchanges are natural monopolies. The more people that go to a particular exchange increases the network effect of an exchange. More people == faster trades, faster trades == more fair prices.
Exchanges will centralize because the economics and network effects of exchanges demand centralization.
With a local exchange, you get the best price for BTC in your city. With an internet-exchange, you automatically get the best price for BTC in the world... INSTANTLY, without having to schedule a meetup.
The more BTC exchanges converge, the better things will be overall. Trades will execute faster, at a lower cost, with maximum convenience with maximum fairness. It is damn near impossible to settle on a price without an exchange.
Its simply a matter of which BTC exchange will be trustworthy enough to hold the title of "defacto exchange of the entire internet".
Counterintuitive, perhaps, but it's happening.
Anyway, the forces of physics can be resisted: A thrown ball goes against the flow of gravity, and even Airplanes and Birds can fly for extended periods of time. But in the long term... almost everything follows gravity in the long term.
Similarly, centralizing market forces (in particular: the formation of "natural monopolies") are a known and documented phenomenon. But in the long term, the BTC Market gains more benefits from centralizing... than decentralizing.
/s
Bitcoin won't die just because people that want to ride the bubble lose some of their investments. It'll slow down, of course, but storing wealth is not bitcoins selling point, and trusted central exchanges are not essential to the model.