About Arvo´s hate
If anyone is to be blamed about Clem getting shot is KENNY, that´s right. Arvo´s case can be easily comparable by those slaughters that happens from time to time in schools and colleges in USA made by low self-esteem, opressed and constantly bullied people.
Kenny was being a jerk bullying, insulting and beating the kid for no reason, Arvo could not fight back and it made him accumulate a inner hate that eventually got out of control, getting him really on edge along the recent death of his sister, so he let it out in a innocent person whom he irrationaly blames for his sisters´ death, exactly like Kenny did when Sarita died.
Kenny´s violence and unstability in this situation were spread like a disease to him, just like bullies create future bullies, making innocent people suffer the hatred caused by the others. So at least try to get in Arvo´s mind and understand what hes being through before bashing him just because he unfairly shot Clem, especially those Kenny fanboys, that should understand it, considering he lashed out on Clem on when she didn´t deserve and made Arvo do the same to her. Yeah Kenny didn´t shot Clem, but he also was´t constantly humiliated with no means to fight back, Kenny just lost a loved one.