Why Do Certain People play League?

So, just got out of a game today where I had an afk, inter, and flamer all in one. The flamer made the afk and the inter. I just want to know why people play league if they simply can't handle playing with a bad team? They should just lean to single player games where they can only blame themselves and not just flame others. Tell me what you guys think about it.

P.S- This was around silver elo which is commonly known as elo hell, but the same thing still applies.