Good grief, helmets, such an emotive topic.
If we remove the emotion and look purely at the statistics, it's more likely you'll damage your head/break your neck falling down some stairs, but I've yet to see a helmet waiting to be donned at the top of stairs, surely this is "Good Common Sense".
Should we not protect ourselves from these "higher likelyhood of risk" activities, prior to jumping onto our own sport/hobby/mode of transport, there are plenty waiting in the wings to do that for us and diminish our rights as road users in the process.
No wonder everyone thinks "cycling is dangerous", when cyclists themselves willingly perpetuate such thinking.
There was a case in Essex this week where a Judge suggested that a cyclist who had been knocked off by a motorcyclist (entirely the fault of the motorcyclist BTW,no dispute), could be deemed to be at fault himself,"contributory negligence", because he wasn't wearing a cycling helmet. Thanks Judge. We can see where you stand.
So somehow by not wearing a helmet you're enticing motorists to run you down and probably deserve it, could this kind of dangerous thinking not be extended to many sectors(rich deserve to be robbed etc).
Let's face it, when I used to Horse ride when I was in my teens, I would wear a helmet and when I used to ride a motorcycle, I wouldn't dream of getting on it without.
No-one will ever have total control of a horse and the nature of the fall and greater height makes you more likely to land of your head. Personally, I'd find a motorcycle was pretty dangerous regardless of helmet (anyroad, doesn't it snap a fair amount of necks given the great mass and speed of the typical fall).
If you want to use a helmet, fair-do's, but please don't preach to everyone else how unsafe/stupid etc they are, unless you have successfully reduced/eliminated all "higher likelyhood" risks pertaining to your environment, though you may end up not leaving your home, which of course should be a bungalow, homes being exceedingly dangerous, stairs 'n all.