This is a mechanism by which anyone could be expelled for saying anything someone else doesn't like. It's a clear policy, which either you support (by attending their events and avoiding saying anything anyone else might find offensive) or not (by staying home and doing what you like).
(I must disclose I have a juvenile and often offensive sense of humor. At events with codes of conduct - and MLH's is based upon a popular one, O'Reilly's contains similar language - I only act myself with people I know who are comfortable with it, and play my filtered persona otherwise. Putting stuff on an event's Facebook group is like being on stage, you gotta be careful of being yourself - keep jokes to people you know.)