In addition to what others said about this only applying to already dead versions of Android, this is one of the upsides of distributing apps online. Nobody is installing an old boxed copy of Facebook 2.0 - google can just ask facebook to remove the hack when they've fixed it, and instantly everyone who installs the app it has the fix, and for anyone else the update is a tap away. This wasn't possible with the hacks to keep old Windows/DOS apps running.