Did you actually read those complaints? Some are about compensation (you don't even have to reach 1000 employees to get those...), some about work/life balance, some about not being as good as the company would allow you to be (!), but i can't see any about emotional abuse, people crying at their desk or having to pay for a parking lot. It's a different scale.

Even on glassdoor, Amazon averages 3.4 vs Google 4.4 vs Facebook 4.4. That 0.6 difference is what you mention: some people will inevitably be unhappy. But that other 1.0, that's not normal for a tech company.