It's weird that HR has to be such an adversarial entity though. One might naively expect them to provide some kind of useful utility beyond protecting the company, even if that's their primary purpose... In my only rather mundane interaction with them, not as a victim or anything, at the suggestion of the office manager I tested the waters with a complaint about people bringing their kids into the office and letting them roam. I still recollect a surreal feeling from the HR rep telling me how they liked how carefully and precisely worded my email was -- it felt like a sign of them telling me they know that I know not to trust them and that my distrust is justified since without such careful wording it'd be trivial to paint me as a parent- or child-hating monster, or whatever, who is the real problem. I got more than I expected out of the exchange (a reminder was sent out to the office that it's against the rules -- not that it stopped anyone the following summer) but the experience alone from satisfying my curiosity on whether HR could be useful with even this one minor annoyance was worth the risk (real or imagined) of backfire.
History and experience tells me the exact opposite - most folks still think HR is there for them, which is the root of many issues.
Organizations are prone to various pathological behaviors, but the individuals in them are still thinking breathing feeling human beings and sometimes they choose to act decently. Be willing to give them that chance.
Corporate culture is very much a zero-sum game, and I think a pinch of cynicism (or heck, realism) can go a long way.