If it were up to me, I'd make owning property with a "party wall" contingent upon membership in some form of home-owner's association, the dues of which are used to pay the dues to such a community fire brigade, as well as things like insurance on the common parts of the building, and such.

I'm not sure how you'd handle delinquency in paying those dues, but it would probably be somehow legally actionable.

EDIT: It's probably somewhat moot, anyway, as the overwhelming majority of these dues-based fire brigades exist in predominantly rural areas, where party walls aren't typically a thing.