Single player doesn't prevent them from being tied to an online service. Even in America, lots of modern "single player" games don't run without a connection to the internet.
These services could easily institute the same limitations on their SP games; forcing them to do online checks on certain events. They could even be sneaky about it by punishing you if you try to evade the checks somehow by deleting your save game, making the game more difficult, or employing other techniques used to dissuade pirates.
They can also do forced updates on software to fix any exploits, run background services that force kill executables, and a bunch of other stuff. Mobile devices are especially well locked down. It just depends on how badly the company wants to keep kids from playing the games. They just need to make it too big of a pain to worry about for 99.99% of gamers, then report the other 0.01% of troublemakers to the authorities.
These services could easily institute the same limitations on their SP games; forcing them to do online checks on certain events. They could even be sneaky about it by punishing you if you try to evade the checks somehow by deleting your save game, making the game more difficult, or employing other techniques used to dissuade pirates.
They can also do forced updates on software to fix any exploits, run background services that force kill executables, and a bunch of other stuff. Mobile devices are especially well locked down. It just depends on how badly the company wants to keep kids from playing the games. They just need to make it too big of a pain to worry about for 99.99% of gamers, then report the other 0.01% of troublemakers to the authorities.