Access control may be a necessity (although in most companies here in France if you can tell a good story to the receptionist she'll let you in without even checking for an id; and if you show an id that's been obsolete for over 15 years, such as mine, and which would be, for this reason, trivial to fake, she'll also let you in with a big smile and a joke about how different you look from your picture).

But wearing a badge? Voluntarily? At all times? In nuclear reactors, perhaps (I've never been there); but in most other businesses, I find this ridiculous and insulting.