I think there should be real world legal consequences for exploiting information systems like this. "Gaming" shouldn't magically exempt a business sector from reasonable protection against fraud and abuse. Just because it's easy to do or involves bits in a computer (that isn't physically on the game developer's premises) should not magically exempt bad actors from prosecution. Yes, it's your computer, those are technically your bits, but this is about how these things are used and the context within which they are.
We have the CFAA in the US, but you'd need a fairly loose interpretation to cover most forms of cheating today. I don't really see the distinction between client and server when the actions taken on the client side cause a dramatic loss in quality of service for other clients connected to that same server or p2p relay.
South Korea has laws on the books as of 2016.
https://dotesports.com/overwatch/news/ow-hacker-sentenced-pr...