Our guild and many others like to make their own chat channels for guild members to congrigate. Quite often non guild members will come in uninvited even though we have it marked with the guilds name and stating it's our guild channel.
There have also been times we've logged into our channel and a non-member is in there and afk so none of the guild members can be promoted to admin. yet this person is marked as admin. so in essence has high-jacked our guild channel. This happened to us just the other day. The person was afk for about 4 or 5 hrs. Needless to say, our guild members were not happy about this.
Having it so player made channels could be password protected would eliminate this.