I don't think they do. A sexist joke is about as professional to make in a conference as a racist or religious joke. Just don't do it. I agree that most humour

I don't think they do. A sexist joke is about as professional to make in a conference as a racist or religious joke. Just don't do it. I agree that most humour will offend someone. Try watching a stand-up act that doesn't offend someone's race, gender, sexual orientation, age, or any other demographic information. Some of those discriminatory jokes can be really funny; after all we're human. There's a time and place for it. Context is everything.