This should be illegal, companies should be forced to open-source games (or at least provide the code to people who bought it) if they decide to discontinue it, so people can preserve it on their own.
If people stopped renting games developers would start selling them again. Until then, the incentive is for them to keep pulling this nonsense.
There's a difference between a game having online elements, such as a MMO, and games that require a connection just so they can keep charging you. Even in the first case though, you should own the client, and ideally it either has a single player mode, or the developer releases the code for a basic server when they shut it down.
That's why I stated that it should be illegal to promise product while selling a undefined time limited license, there should be a clear minimum time stated when you "buy a subscription" for (single player?) games.
Fair, stating a time-to-live when you're paying might make some people think twice. At this point though, I think people need to just not be paying unless they get to keep it permanently. Paying for access to the online portion is fine, but the rest should keep working and you should be able to get your data out of the developer's system.