To be honest I don't blame them for the initial anger at Nasri, it's more the months and months of abuse via Twitter that followed. Some initial venting of frustration that their player of the season (I don't know if he was officially, but I mean he very arguably was) leaving straight after finding by far the best form of his spell there, is perhaps to be expected. They should ideally be directing some anger at their board though, for thinking it is ever, ever acceptable practice in modern football to let the contracts of key players run down to one year left. That is one thing that totally flys in the face of them having good business acumen, which is supposedly the one positive thing you can actually say about the people who run that club. But I guess it's knee-jerk to focus some ire at the player as well.
I'm fairly sure they're still giving it out via Twitter though, and that's just desperately pathetic.