It was traditional (for a couple of decades anyway) for most cars (including all Australian-made ones) to have automatic chokes that just used exhaust heat rather than electric heating. Occasionally on old cars the heat pipe orifice at the carburetor end would clog up and the choke would stay on until someone cleaned it out. I seem to recall a few used electric heating instead, but AFAIK the reliability was worse, not better, in the long term. The main problem the auto chokes had was that some tenant would rotate the movable part of the housing slightly, which adjusted the choke setting. The setting was critical to a fraction of a notch on the outside of the housing, so usually home-adjusted ones worked badly thereafter. It was very rare for there to be any legitimate reason to make an adjustment.
Achieving reliability is mainly a matter of controlling the maximum temperature of the bimetallic coil. If it is exposed to too high a temperature, it is ruined quite quickly. Hence the tube with a small aperture at the choke end, used on the car auto chokes. The housing around the coil was also a heavy zinc casting, to provide the necessary thermal inertia so the choke would not be applied until the engine had cooled completely (which takes a very long time for a water-cooled car engine).
Of course for the past thirty years very few cars have had carburetors, and mixture enrichment for cold starting is controlled by an electronic temperature sensor.
