Who is at fault? (Poll)

I'm going to make this simple. The rage quitter complained/raged for the entire first 10 minutes of the game, blaming everyone, just being generally toxic for no reason. The farm stealer was taking blue buff and the rage quitter started walking over to take it. The farm stealer pinged him back, and told him no. The rage quitter stood there, waiting for it to be low, then sniped it. The farm stealer then went mid lane, and took a wave of farm. The rage quitter screamed, then rage quit. Who is at fault for him leaving?

Edit : How do you get downvoted for putting up a poll?