They're naturally hostile towards outsiders after what the Nords put them through.
(Plus the devs didn't give any choice...)
True, but honestly, with half bird half lady witches giving them orders, I don't think that it would end well no matter which way the wind blows. I tried REALLY hard to feel sorry for them, and even helped their 'king' escape, but in the end, half way through the dwemer ruins I turned on em. Their really not worth the time.