User blog comment:Xilinoc/Ch. 543 - Letters/@comment-2211792-20130626143149/@comment-1387259-20130626171609

I still think he as some ulterior motive. Yes, he's a Quincy, and he has shown hatred for Shinigami (though he's grown a little tolerant, but that's not important here). By allying himself with the Vandenreich, he's turning his back on everyone he was allied with in Karakura, including Orihime and Chad, to whom he's at least shown some level of concern.

Uryu wouldn't bat an eye if someone said to him "Kill Ichigo," but he'd certainly hesitate if someone told him to betray his other friends.