I don’t think that providing never-ending service is likely practical.
Certainly not if the game doesn’t have an ongoing service fee of some sort. World of Warcraft players pay a monthly fee, and so as long as they can keep the thing in the black, they can keep it going as long as they can cover costs. But outside of that sort of thing, unless a game provider who provides ongoing service can make money by extracting information from player computers and data-mining players or something like that – not something that I’m really keen on encouraging – there’s inevitably a point in every online game’s life where service is gonna end.
I could see maybe an argument for, at purchase time, clearly-designating games that have an online component and thus will stop working at some point, so that the consumer can decide what he wants. There are some genres that just don’t work offline, but outside of those, it’d let a consumer more-readily choose offline games.