Does anyone know why they designed the games so that Chuck and Frank don't directly kill any psychopaths in their cutscenes? The closest they get is causing them to bleed out. But the vast majority die through their own mistake or some environmental danger.  
 
Would you guys have preferred Frank or Chuck to deliver killing blows? Or do you like the way they handle psychopath deaths right now?

I guess they would rather not force your character into doing something like that. It is your choice on what Frank or Chuck does. So for them to show either of them doing something that you don't agree your character should be doing makes it seem like it isn't your choice anymore. So rather they leave them neutral through a conflict. You are confronted by the psycho and then you have to either flee and stay away, or fight back. But when they psycho goes down it is time for you to leave. 

They want to reinforce that Chuck and Frank are good, sane, well-adjusted people that would only bludgeon non-zombies to near death I suppose. I think it's fine, in a completely meaningless way. Actually, come to think of it, I don't think I would like them actually killing those people. So violent.

I think its because your character is generally suppose to be a good guy, this leads him to try to rescue survivors instead of just hide from the zombies. 

Would you react differently to Chuck if you put a Drill Bucket on the head of actual human against a zombie?

It's a Karma thing. They are their own undoing. You could read in to it as having some deeper meaning like a lot of the stuff, or take it at face value as cliché retarded stuff.