User blog comment:IamJakuhoRaikoben/Chapter 291: Naval Battle, Review./@comment-5032699-20120713070452/@comment-904888-20120713101549

They acted like that because it was Natsu who invaded their lodging a few nights ago, and gave them a lecturing, which so far suggest that only Rogue is affected in anyway. ST were already arrogant enough to begin with. But now they have found a 'target' that they can 'shove them in their faces', hence why ST acts like that to FT. Lucy was probably unlucky (or else Juvia was just simply lucky) to have been the sole target of Minerva's rage.

Yukino is an oddity, Arcadios is shown to be extremely surprised that the final TWO keys are at the GMG as well, which he probably should have known if Yukino was indeed Arcadios' henchwoman. So far everything points to No. She seem genuinely broken when she was humiliated by ST (which could have been acted), but she is shown to be rather moved when she heard someone invaded ST's lodging (something I highly doubt was acted). Yukino simply may have military connections in the past and knew the correct salutation to a higher ranked Arcadios. Also, she never reported her 'rank' when asking for permission to speak to Arcadios.