The value of money is subjective. Governments drain the value of fiat currency by printing and spending. This causes people to subjectively value the currency less, which makes its market value go down (inflation.)
There are several reasons why this is not the case with Eth/DAO:
1) Every fraction of Ethereum is accounted for in the public record.
2) No additional Ethereum was created to compensate the losses of investors, only the original stolen Ethereum is being returned.
3) No politician's pockets are being padded, the only receivers of value are the rightful owners of DAO Tokens. (Only ETH was stolen, not tokens - everyone still has their tokens.)
4) If some government took this as precedent to force a bail-out in the future Ethereum Ecosystem, based on the standards of the Ethereum community, the value of Ethereum under an actual government-instituted bailout would plummet. It goes against everything we believe in, and the subjective valuation of Ethereum on a mass scale would plummet, effectively making any funds doled out worth only a fraction of their value by the time the receiver had any chance to use them.
I could go on giving more reasons, but is it really necessary? No one should be attempting to make analogies between fiat currency controls and an Ethereum fork unless they've considered both the philosophical and economic implications of their arguments, and it's obvious that most anti-forkers haven't bothered to give due diligence to the question of what's really at stake here.