People that use shared city-bikes irregularly (like me.) I don't always go out expecting to use a bike, but life isn't always predictable (subways busted, cabs not available, unanticipated change of plans, etc.)

> I rode a bike for 2 years in downtown Toronto, wearing a helmet the entire time, and never once did I think that the helmet was inconvenient. You carry it up to your office and leave it on your desk. Or you turn it upside down and it's an adhoc shopping basket. Or you clip it to your backpack. Or you loop it through your bike lock.

Good for you for not finding it inconvenient. That doesn't mean that other's also don't.