Fortunately for you, if these things bother you and you'd rather have a malleable money supply managed by unelected officials who can seize funds and reverse transactions at will: you are well served with the current monetary paradigm - be it Keynesian, monetarist or neocon - the differences are of cosmetic character, really.
Those of us with the (obviously wrong!) view that a monetary system should be predictable and not prone to manipulation by individuals have been longing for the chance to try out something like that. It will quite obviously fail, because centralized systems run by
experts are naturally superior to decentralized systems run by no one but some people just need to convince themselves on their own, deferring to the wise opinions of experts is not enough for them. And who knows - if by some freak accident such a monetary system turns out to be better than what we have now, you will benefit as well

My preferences are not important. The point is that a system that does not allow the forcible return of stolen property will not be acceptable to society, except for thieves and other criminals. In the end, it will be rejected even by the libertarians who now think that irreversibility is a good thing.
The answer to that one is really quite simple: the raw transfer mechanism is irreversible, which is a byproduct of the 'no authority has complete control of the network' property. Should Bitcoin become the backbone of global financial transactions (or get near that state), it'll simply mean that a vast number of escrow services will be developed (some automatized, some with a human in the driver seat).
It's not that Bitcoin is perfect, or even that irreversibility is always a good thing: it's a necessary consequence of an extremely efficient, distributed and owner-less (your term

) system that in principle can be unrivaled in its low transfer costs. Escrow will add to that, but at least for most (small) transactions, automatized, or at least extremely streamlined escrow should be enough, and probably won't raise the cost above the fees taken by credit card companies or banks.