Eternal Edge

Because it's fun.

You get the opportunity to bait and outsmart 5 other humans in an environment that isn't life-endangering or illegal. And even if you lose you can just try again.

Eh, whether or not it's fun is sort of subjective.

I would enjoy the game more if the community wasn't total shit, they tend to sap all of the fun out of the game.

I'm not saying every LoL player is like that, but from my experience the vast majority of them are elitist asshats who don't seem to understand that it's a god damn game.

The community really makes it hard for new players to enjoy themselves.