That's because Most likely he won't be banned.

Threatening to ban someone verbally / in chat just makes you look like an idiot. Mute them, and report them afterwards. There's no need to tell them. Half time the you'll look like a crybaby anyways.

What if there's a chance he'll stop calling you names or not go afk because he's afraid of being banned?

uh this guy kind of has a point... competitive gaming whether or not they ban them will continue to happen, and if little things like this annoy you the chances of you finding consistant enjoyment in such a community is very unlikely.

Umm...except that this is THE INTERNET where every1 here is ANONYMOUS!!!!!

People know they can get away with saying rough things because they know you cant do anything about it...

How hard is this to understand?

Except that you're not threatening to never invite them back to a game, because (1) unless you're playing a lot of ranked on a slow day you're probably never going to see them again (2) Reporting and ignoring players doesn't prevent them from getting matchmade with you or anyone else and (3) If the person is really angry or trolling enough to afk for the whole game, they're not going to care. Basically, your analogy is "fine! I don't want you to play soccer with us anyway!" while you're in a giant park with thousands of people looking for one more guy for their soccer team and aren't picky. And you might be forced to play with them anyway because your parents and his parents go to the same parties.

Though, given that Riot either rarely enforces bans or simply gets too many reports to actually deal with it (I assume frivolous reports are rather common), it's less a mom and more a distant authority figure who's processes I don't fully understand. So I guess it should be "I'm telling Dad!"

just report at the end of the game, no need to make a scene.

There is no chance. That's the internet. No one is going to take any insult without replying because on the internet, YOU are the man.....or so everyone thinks.

Click report, fill it out, reported player gets added to a "do not play with" list on the reporting summoners profile regardless of the decision RIOT comes to, said player never has to play with that particular ass hat again.

Problem solved and all with just a few lines of code.

However, if it's at a local gym that has a rule against drinking/eating (trolling, feeding), and you tell the gym owner (Riot), then it matters a lot more because they are actually in a position of power.