They are trying to keep up with the demands of Facebook, but are failing miserably. If you interview for one job, by the time you are hired, your job title and specifications will have changed so often that you have no idea what you are hired for. Every position is being created on the fly. When they change department or position names, they do not delete old documents with those titles. So, you have instructions that contradict each other.
You are hired as salary and are expected to put in far more than 4p hours a week. If you don't, you are treated like you are not a team player and have a low work ethic. However, if you are working the 40 hours a week you are hired for, there should be no harassment beyond that just because co-workers are willing to devote their entire lives to their jobs.
Oh, and if you report a manager and have actual proof of their short comings, expect to get fired immediately.