When you view an area, the edit icon is both available and clickable, taking you to the edit panel for the area. I don’t know if anyone can save their changes, but it is available, and probably shouldn’t be. 
I couldn’t resist checking this with a low-impact edit, and I’m pleased to report that, although it looks like you can edit (which might be less than optimal from a UX standpoint), an attempted save results in an error in red: “Area is not owned.”
So that’s good from a security standpoint, but it probably still shouldn’t let you get to the edit page if you don’t have permission to save said edits.
That is a bug indeed. As @Tlancaalek, not a security critical one, as the backend does not allow edits, but yet one that needs fixing.
I tend to not see those sort of bugs as I am mostly logged in as admin, which always has edit permissions