If a civilization has portable nuclear fusion (plug your spaceship into a suitcase for power), then there's no reason to hang out near a star. People living inland never think about how to obtain salt anymore.
Nuclear fusion is not magic infinite energy; the amount produced is limited by the amount of fuel being used. I mean how much power is generated from fusion anyway? Especially at the scale (suitcase) you mentioned?
I dunno where your remark about salt comes from either; a lot of salt intended for consumption is dug up from the ground (salt mines).
