I read some other comments in other sites. Two pretty common comments there are :
1) relative to other factories in China, Apple's condition is already much better than others.
2) in any competitive industry around the world people are working long hours and like a slave anyway. I for one can't count how many 16 hour day I did in my job. True I got paid better but other than that a lot of us don't feel the respect and appreciation from our employers anyway.