Diablo Game Questions How long will Diablo 3 stay online?

How long will blizzard keep hosting the servers for diablo 3?

I don't think there is a way for them to make money off of this other than the base D3 purchase and ROS "DLC" that was a while ago but that's it.

Is that really enough to keep on hosting the servers for such long? Even free content once in a while and updates.

Also i'm sorry if this question is not allowed here, i read the rules and made sure it's on topic. So if i might have missed something, my bad..