"I did more damage than you, means I was more useful"
Well, you are a laner. You are literally sitting in place hitting the opposing laner with abilities whenever you feel like walking up and doing that. I play jungle. I only hit champions when I go into a lane or randomly find them somewhere. How in the world do you think that damage to champions is comparable between a laning champion and a jungle champion? That's like saying a catcher in baseball is a better player than the 3rd baseman because he catches the ball more times in a game...
Can we stop using damage to champions as a way to say who was useful in a game and not?