The difference is that I don't think that LaBate's intention was to deliver a punishing blow to Haula. While it was a hit from behind (which is a minor penalty away from the boards), it wasn't a check that was intended to drive Haula into the boards. Part of the issue was that Haula was at the worst possible distance from the boards - too far to avoid hitting the boards all togeather, but not close enough to be supported by them. Like I said, all of the ingredients were present for that to have been a very bad situation if either Haula was less situationally aware or if LaBate had delivered a stronger initial check.
On the other hand, it was clear that Barnes' intention was to lay a punishing hit on Serratore (or any gopher for that matter) and when you do that you had better be **** well sure that 1.) you don't charge and 2.) you hit the other player square in the torso. Even without the contact to the head, Barnes was guilty of charging (which may very well have been called a major anyway) all the contact to the head did was what insure that he was given the major.
Again, neither play has a place in the game and the only person responsible is the one who made the decision to deliver the initial check because by doing so they transferred the resulting outcome to the refs judgement (regardless of what that judgement is). No hit and the ref has no decision to make.