"continued to express these, contributing to a workplace climate where say minority ethnic or non Christian staff felt unwelcome, unvalued, undermined or threatened?"
I doubt that she would do that, but if she did, then she should be disciplined for it.
"Using words like "snitch" and "grass" sounds more like children in a playground rather than an adult working environment"
I am sorry but I think that things said in confidence to you, even if stupid or offensive, should not be held against a person. I remember at primary school, we had a song "tale tale tit ...." and I have never forgotten it. I wouldn't tell on someone over something said off the cuff.
"I manage staff and I would be extremely disappointed if I found out that something like this was going on, but other staff felt it was better to either ignore or handle it softly themselves rather than work within company policy for fear of getting labelled a "snitch." Geez."
Well that is where we are different. I don't like dropping people in it over things said in confidence however stupid or offensive. I understand that people say and do stupid things and I am prepared to give them a chance.
Not doing so will backfire very badly one day. If you frighten people and persecute them for making mistakes then one day by the law of karma, things may turn around 180 degrees.
One reason for the rise of UKIP is that many people feel that they are not free to express their opinions and may lose their jobs even over silly things they may say. I listened to the MPs debate the other day and an MP said that his constituents told him that he was able to say things that they were afraid to say. The problem with that is that it builds up a silent resentment and has the danger of one day reversing totally by the law of karma, in my opinion.
I don't believe in draconian consequences, draconian dsicipline or people being sacked over silly things they may say. I believe in giving people a chance, by telling them that they should not say those things and letting them change.