Unfortunately hindsight is a great thing, you always wish you'd done this or that AFTER some scum bag ruins your day! The fact is, some people will steal anything nowadays, whether they have a use for it or not. Look at how many priceless videos of weddings, etc., are stolen when thieves steal VCRs - they probably just get dumped so it makes you wonder why they bother.
I'd say the helmet would have finished up in Cash Converters the following day because even if it was old and scratched, it would most likely be worth something.
The main reason I never leave my helmet with my bike unless someone is staying with the bike is because I'd worry about someone knocking it over and damaging it. I've seen countless helmets fall off bike seats, get kicked on the ground or knocked off a mirror, and half the time the person who does it just puts it back and doesn't say anything. Great if you come off later in the day and find the helmet offers you no protection because it was already damaged. And I never leave anything portable on the bike unless I am sitting a few feet away and can keep an eye on it.
It's just a fact of life that you don't leave anything lying around because it's more than likely that someone will lift it. I've heard about kids breaking into cars to steal $5 worth of parking money left in a tray.
You say you have no insurance? Firstly, shame on you! Secondly, if you mean you have no bike insurance, but possibly have contents insurance, your helmet should be covered under that as it is classed as clothing and as such is covered when you are away from home.
Yes, I am pedantic about spelling and grammar so get used to it!
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