Why does that bother you? Putting this instance aside, I am not aware of a single person who believes legality defines morality in 100% of cases. Furthermore I have not met a single person who does not believe at least some illegal events were morally justified, for example most americans believe the american revolution was justified.
When you say things like I can’t understand why you would not think X, when in reality it’s very understandable why someone would think X, you come off as just trying to use a logical fallacy to argue that everyone should bend their morals to yours.
It's because their actions exposed illegal activities that various governments were partaking in. The same organizations which define what a criminal is, and are supposed to be held accountable to the people. Having people that are above the law is of course a dangerous precedent. To boil down to a stupid thought experiment, why should Assange or Snowden be prosecuted when the people who they exposed blatantly exposed breaking the law were not?
When you say things like I can’t understand why you would not think X, when in reality it’s very understandable why someone would think X, you come off as just trying to use a logical fallacy to argue that everyone should bend their morals to yours.