Why do some (or adjectives?) St John Ambulance staff/volunteers enjoy military-style titles?

I've been in touch beside some people from St John Ambulance, and one of them has the title " Divisional Superintendent for [place name] Cycle Responder Unit.... And another have the title " Corporal [name] "...

Why is that?

Also, St John Ambulance Cycle Responders have this black thing on their shoulders which I can't read ( http://www.bbc.co.uk/derby/content/imageā€¦ ) , do they own so sort of ranks or something..?

I'm only asking because I'm about to join'em hopefully surrounded by September - but too curious to wait to ask them myself then.. LOL
Answers:
The St John ambulance and the St Andrews ambulance volunteers enjoy title like that. I know a Commandant in the St Andrews. I instinctively don't like the title and I am myself a volunteer first aider with the British Red Cross who don't enjoy title like that. It is a ranking structure.
They're based on the British Army!


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