I really think this is a bad move on Riot's part. Players should have a choice. Riot has always really done their best to their community and I feel like this is going against your nature. It's really a horrible thing to do and I REALLY hope you can revoke this.
Although this doesn't effect me personally, one of my best IRL friends is Singaporean, and although neither of us live in Sg ATM, he is moving back in the near future - and therefore going to lose the account he worked hard on. Furthermore, his brother lives in Sg ATM and he simply won't be able to play with him. My friend is considering quitting NA LoL BEFORE even the new SEA servers are up, because he is talking about how 'pointless' continuing to work on his character here is.
Secondly, my friend received an email, supposedly becasue he put Singapore as his country somewhere in the sign up form, even though he doesn't live in Singapore at the time. Is he going to get kicked out anyway, even while he's NOT in SEA? This seems absurd, although I doubt it's how it will work.
Either way I think this is a VERY bad decision on my part, and no amount of money that this SEA publisher might give you is worth the pain you're doing to your community.
As a company that prides itself on being so community orientated, I was honestly surprised that you could make this mistake (again). I suppose the community outcry when you did the same thing for the EU servers did not tell you anything?