Satoshi created a currency unit without a central party being necessary to prevent unit duplication.
And you want to tell me it's impossible for centralized exchanges to build a clever system that enables users to have some form of control over their trading funds? Well, perhaps it is.
The fact that it is centralized means that if the server(s) is in fact potentially compromised of course they can't let you control your funds because how should they know if your actions are legitimate or not?
Cold storage
should ensure that in a worst case scenario most of the exchange funds are safe.
This incident will reveal if bitstamp can be trusted further down the road. We can expect a more thorough audit and if indeed only the hot wallet was compromised and users who lost funds are reimbursed
it will be a good thing not only for stamp but for confidence in bitcoin in general.
Now if that does not happen we can expect gloomy times ahead.