Important points Austin, but I'll disagree a bit on two things--and I hope I'm not being a "homer" here.  First, Allen's recent transgression was blatantly intentional, and happened after he'd been beaten by the opponent.  But far worse, for me, was his out-of-control behavior on the bench.  He looked like he'd have seriously hurt someone if an assistant hadn't physically restrained him.  'Roid Rage came to mind, and the guy is pretty pumped up.  I thought one game was a truly weak punishment, and Coach K's comments after the incident even weaker.
With Brooks, it appeared he was pulled to the ground, a possible over-the-back that wasn't called, and the WSU player was straddling his legs, so lifting his (while absolutely not okay) was more a reflex.  As you say, he's emotional and does play "on the edge," but I too wish for a stronger response from him and his coach--especially after the tragic incident a couple years ago.  I just see it as very different from Allen's behavior.