As a teacher, I have to agree that it gets really old having to raise peoples' kids for them. They don't discipline at home and have no structure in their lives at all. So this leaves the burden on myself and other teachers to discipline kids and help keep them from anti-social beahaviors. That being said, because the parents are afraid to discipline I am as strict as nails in my class. I some times say that my ninth graders are not allowed to breath unless I say so. It makes for a very ordered classroom with few, if any behavior problems. I wasn't always like this. When I first started teaching I governed by hippie nonsense that we learned in our education courses. I learned quickly that such silliness does not work. Each year that I have taught, I have become stricter and stricter. The result: My students are very well behaved in class, are becoming more independent learners (not relying on copying the paper of the student in the next desk) and my students grades and scores have improved.
So, I say, "Yes, wash their mouths out with soap when they are disrespectful, curse, or say unkind things to or about others."