I'm not a huge Brett Lawrie fan, but I don't see what the big deal is. The Jays haven't made the playoffs in a long time and the A's have. He's going to a situation where he's being asked to replace a guy who is much better than him, and is understandably trying to say things that will endear him to Oakland fans who are most likely pretty jaded by this deal.
He also made an eloquent shout out to the Toronto fans. If this is his "miffed" reaction to being dealt, it's pretty tame, by Brett Lawrie standards.