Remember that the law defines harassment as conduct ‘known or reasonably known’ to be unwelcome. An employee making crude comments or telling off-colour jokes in a lunchroom for example may garner laughs from some, but that does not make that sort of conduct appropriate, and it does not mean that it’s not harassment.
What it does mean, especially if others are laughing, is that the person who was intimidated or made to feel uncomfortable may hesitate to come forward. Employees often feel helpless in the face of harassment, especially if they are worried that no one will believe them or take them seriously. This is why workplaces are required to have a reporting system in place to receive complaints of harassment, so that employees can feel confident that their complaints will be taken seriously and dealt with appropriately.