Or "RENT", explicitly stating that you are renting access to the game for a fixed period of time.
After all, "a licence to use the game" is being violated if you can't use the game any more due to it requiring access to a server that no longer exists.
If a game is no longer commercially viable then they should be required to release the server components and/or the source code, allowing anyone to create their own server. Since by their own admission it's not commercially viable they wouldn't lose anything by giving the server components away for free.
This has worked well for games like Quake and Doom which remain fully playable today, even taking advantage of modern hardware which did not exist when these games were developed. It also generates (some) continued sales as although the source code is free, the game assets are not.
If they shut off needed servers and render a game unplayable, then not only do they guarantee no further sales whatsoever, they also generate bad sentiment among former players, and turn all physical copies into completely worthless e-waste.