Working backbreaking hours with bad work/life balance is considered unGoogley. There are sometimes when people burn the midnight oil, but in general Googlers don't work 60hr weeks.
I think the primary difference may come down to a culture of secrecy. Openness breeds cross fertilization, couple that with very few restrictions on Googlers in working on side projects, open source,and collaborating outside Google and it it's easy to see why so many Googlers are lured away by the allure of startups.
As for Googlers being unhappy with their projects, there's two answers. One, google culture permits challenging your management and product vision even as far as calling out VPs, so people here are constantly voicing their criticisms instead of falling in line. That can breed dissatisfaction especially if your criticisms are later proven right.
The other is that Googlers switch products often when they get bored. It's easy for people to get unhappy when you switch from development to maintenance. I think this is very healthy,enduring people working on a product are enthusiastic. If your jet collecting a paycheck while dreaming of more interesting stuff better to go do interesting stuff.
The level of secrecy and compartmentalization in Apple sounds like hell to me.