Because the Empire blow up a planet full of pacifists for no other reason to scare people. Albeit, the Empire has better music. Given it's multi-ethnic, multi-species and led by two women....yes? The Quarrens in the EU notably sided with the Empire and the Empire backstabbed them because, hey, Empire. They are altering the deal. Pray they don't alter it any further. Notably, this is actually a plot point in TTT. Bel Iblis totally believes this is going to happen and Mon Mothma is a secretly sinister figure. So her coldness and aristocratic actions are deliberate. It's just Bel Iblis is incredibly wrong.