VFB Pro not well secured !

Not quiet sure but I think I found a bug that enable users to add new items to lists without permission.

Details:
Say you have a list of selections in the form. Just discovered that in the front end, anyone can use “Inspect Elements” tool in Chrome or any browser to inject/change items in the list. I realized this when I start noticing some weird selections I never added as choices to that list.
This is not supposed to happen am I right?