Both Volchenkov's hit on Gagne and Carcillo's hit on Karlsson were clean. If you see the guy coming and turn your back at him, like one guy said earlier, its as bad as diving.
Nobody should have to drop the gloves for a clean hit. If you make a dirty play, you should be prepared to have to drop your gloves, and if you don't, you lose any of my respect that you still have left after the dirty play. Volchenkov's hit was clean, you could even say that Gagne brought it on himself, so I don't think Volchenkov had any obligation to fight.
On another note, I don't even give Pronger the dignity of calling his Elbow on McAmmond a bodycheck or a hit. It was a dirty elbow, not a check, not a hockey play.