That residual fat is leftover from what you cooked in there before, so it would only be an issue after cooking something with a very low smoke point, washing the pan, then cooking something with a high smoke point.
Wiping the pan with a paper towel will get rid of the vast majority of this, and if you dry it over heat you can carry on to cook off the last little bit, like a sort of half-baked or top-up seasoning. Doing this before storage gives the smoke smell time to clear before you next use it, but this should be minimal if you cook it off gently. I recommend turning on the cooker hood extractor if you have one.
I like the heat-retention of cast iron but I've gone over to enamelled (le Creuset). I still use a carbon steel wok that needs reseasoning after using the traditional metal spatula, so I actually rinse, dry with heat, wipe over with oil and heat.