It's Facebook we're talking about. Probably one of the most un-ethical entities on the planet. Of course they won't respect their employees, they don't respect their users (or their users' privacy) either.

If you decide to go and work for one of these companies abuse in some form or other should be expected, and you should be well aware that you are in some way acting against the interests of the general public and that when the company decides that you are to be disposed of that it will do so without consideration for your well being.