What I don't understand is why Riot doesn't figure out a way to sub-in new players when someone AFK's - this is how it's done in many other MMO's - the solution seems simple to me:
If you join a game late you get awarded an average amount of gold + level based on how you usually perform in-game (perhaps averaged out over your last 10-20 games)
That way, someone AFK's, they get booted instantly and automatically (within a reasonable time frame of say less than a minute) or a team can vote to kick someone... also a great way to deal with toxic players too - kick them and have someone else come in to pick up where they left off...
Perhaps you could earn an XP bonus for being willing to join a game late.
The LeaverBuster is ok, but what about people have real lives but are expected to always be able to finish a game? Something comes up in a 30-45 minute time frame you have to deal with an automatically the other 9 players have to suffer. Just sayin'