It's not the offers for players he's railing against, it's the general assumption that the player is already theirs. For example, see the repeated quotes from the Barca players saying Cesc has Barca DNA, etc etc.
Well, that's Cesc's fault because he said he'd be willing to go to Barça. Plus, stating that a player born and raised in Catalunya, with Catalan parents who still live there, who played for Barça at youth level and who is a Barça fan has 'Barça DNA' (Whatever that may be) is not really unfounded.