1) The softball game analogy is not changing the subject. Just because the game is on the internet does not mean that good sportsmanship does not apply to you. That is not to say you cannot criticize your peer's moves, but you have to be constructive. Your basketball analogy fails on this level, because even if that coach is reaming you out, his goal isn't to shovel his frustration on you. Its to tell you what you did wrong and how you are GOING to fix it by the next game.
Sportsmanship, manners, etiquette, whatever you want to call it, has come to be expected in our game. Our community wants the shadows and reputation of its shady past to be shed and for us to be in a comptetitve, but social and fun game. Yes, I understand losing sucks. Losing is frustrating. Losing is not fun. That tends to be the definition of losing. However, you aren't a professional player. You're playing on the equivalent of the sandlot. Eventually, if you are an ass to everyone, everyone is just going to take their ball and go home. Well your ban is Riot taking its ball and going home.
2) I still don't understand why this whole "competitiveness" argument is seen by people as an effective excuse to poor sportsmanship. Other sports, hobbies, interests, there is a shared respect for others that take part in the interest. I want to be able to walk into an elevator and talk to two other people that I overhear talking about League. I have in the past had that experience, and face to face its wonderful. Get that guy behind a computer screen and all of a sudden you have someone with the attitude of the clone of Jozef Stalin. What is it about anonimity that breeds this asinine behavior.