Looking at the verse in question (Exodus 35:3), I notice that it comes in the same breath as "Six days shall public business ("work") be done". It's safe to say therefore that if your work requires you to "kindle a fire" as part of your "public business" (read: smithy), then you're not supposed to do that, as that is engaging in work that you expect to be paid for.
Like you Royce, I don't pay anyone anything on the Sabbath day - I make no purchases, and I pay no bills. I can also guarantee you that there is some form of Robot/Computer that continues to make sure that you are provided with Electricity and Gas, even when there's no one there to feed it anything. I currently work for a company that provides support for "building management systems", which are essentially computers with some software, attached to building appliances (including those in a Power Plant) that tell them to come off and on to a specific timing schedule. There are, rarely, people at these plant-sites on the Sabbath day - they're all pretty much Computer controlled
Furthermore, how would this apply to someone to lives in a cold climate? Are they not to re-light their fire that they use to keep warm, just to keep this supposed "you can NEVER, EVER have a fire!" injunction, whilst they freeze to death? I don't think that was Yahuweh's intention with this instruction here. Furthermore, I think the fact that's it's linked to the teaching regarding not doing ones public business on the Sabbath day is a strong indication of what type of fire Yahuweh had in mind.
This quote from the Theological Wordbook of the Old Testament
also gives us some insight to the word ba'ar translated as "kindle" by most translations of Exodus:
Of the several Hebrew words which are translated “to burn” two are most often used figuratively. These are bā'ar and ḥārâ. The others, such as śārap, yāqad, and yāṣat all have to do primarily with literal burning, whereas these two are commonly used to describe anger, passion, intrigue, etc. ḥārâ is confined almost totally to usage with anger, while bā'ar stresses the consuming and contagious qualities of fire especially in the religious (aka 'cultic') context.
Also, how would a Levite Priest consider this instruction, when he is also commanded The fire on the altar shall be kept burning on it; it shall not go out. The priest shall burn wood on it every morning, and he shall arrange the burnt offering on it and shall burn on it the fat of the peace offerings. Fire shall be kept burning on the altar continually; it shall not go out.
(Leviticus 6:12-13). So the Levite Priest has to make sure that he "never kindles a fire" on the Sabbath day, yet make sure that "every
morning" he continues to keep the offering fire going. What if it goes out (which it isn't supposed
to do - but I bet it did)? He'd be in a right pickle!