The other thing about Twitter - apart from footballers being idiots on it - is that many footballers are clearly using it as a tool for self-promotion.
@cesc4official has some poor schmuck translating every tweet into Castilian, Catalan and English. Don't think it's Cesc himself.
I think once they make gestures on Twitter that indicate they're operating not in a private capacity but in their public personae as football celebrities, those tweets become fair game for public discussion.