Mean People Suck

My oldest child is a middle school girl. Unfortunately I have recently noticed some "Mean Girls" type of activity going on at her school. This kind of behavior is pretty typical of adolescence. I'd like to think that most of these kids will grow out of it and mature into secure, compassionate, productive citizens. I have met too many petty, backbiting adults to take this for granted though. I would also like to think that nurses would be above this kind of childish behavior. In nursing school I heard the saying that nurses eat their young, blah blah blah. I figured I was too nice and too hardworking for anyone to want to eat me up. Wrong. I've encountered a few cannibals in my time, but I'm not so young anymore, not so vulnerable.
I talked to a nurse the other day, however, who reminded me of this issue. I FINALLY took the 12 lead class I have meant to take for like five years. When I walked in, there were already about ten people seated in the auditorium. I smiled in my generally smiley way at everybody, and only one nurse smiled back at me. I recognized her as an RN who used to work on our Orthopedic post surgical floor. I had encountered her in the past when bringing patients to her from PACU. She had struck me as extremely hard working, smart, and helpful. A couple of us had suggested she come to the PACU, but she would need some other experience first, either ER or ICU. So, as I talked to this woman, we'll call her Nicenurse, she told me how she had transferred to the ER to get some experience there in order to hopefully eventually work in the PACU.
I have to explain: like so many others across the country, our ER is a zoo. It is a chronically understaffed, inner city, outdated, underbudgeted, overburdened mess. Staff turnover is horrendous. It hemmorhages nurses like a torn aorta. I know several agency nurses who refuse to go back. They seem to get a new Nurse Manager on at least an annual basis. I already liked Nicenurse, but I know how chaotic our ER can be. Now my respect for her has gone up substantially.
 She is so discouraged, though, she tells me. She has been in the ER for ten weeks and has no intention of quitting, but she says that the other nurses and the techs treat her like crap. This puzzled me, as I know she is hardworking and smart. Nicenurse told me that fellow ER staff criticize her positive attitude and are making bets on when she will quit and who can get her to quit. Apparently other staff have refused to help her at times and have told her incorrectly where items were located. I had no reason to doubt her story, but I just don't get it. In my mind more staff = good. I would want a decent nurse to come on board. Maybe if they could retain some more staff every nurse would not have to have 6 or 7 patients, including ICU holds.
I hope things improve for her. Do other professions treat themselves this way?