Point is Rosa Parks refused to give up her seat expecting to get arrested. That's civil disobedience. What Snowden did was not civil disobedience, it was vigilantism.
Parks wasn't trying to hijack control over the bus. She was violating the seating rule to make a point about equality. Snowden on the other hand just decided he had the authority to unilaterally declassify classified documents. It isn't a valid comparison on any level.