Hmm. I just checked the source, and you're absolutely correct on the menu item still being displayed. This is related to the new "Shout Chat" that was added for 7.6.0, which was a full page view of the "Shout Box" side-bar/portal island. As you've pointed out, the menu item should not be displayed, especially when the user wont have access to the ShoutChat/ShoutBox content anyways.
I've added it to the list of bugs to be fixed for the next version. whk, thank you for reporting this bug
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protip: ShoutChat could be setup in such a way that only the administrator and moderator groups could have access to it, giving them a real time "instant messenger" style of chat.