This isn't going to change until the standard of living in China is higher.

Not only does Apple know of the working conditions, so do the workers before they work there. Sweatshops are horrid places, but, generally speaking, they are preferable to the options available to those who work in them.

It is an interesting political dynamic here, though. From time-to-time it seems Apple, and especially the late Jobs, has been held up as an example of conscientious corporatism. The athletic shoe companies could only dream of getting the happy press Apple has. Yet even moral Apple isn't paying First World wages and providing First World working conditions in the Third World.

“Nobody has a legitimate reason to fear a faithful interpretation of the Constitution, and nobody has any legitimate reason to fear effective and complete protection of civil rights." - Alan Gura